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As filed with the Securities and Exchange Commission on December 22, 2004

Registration No. 333-           

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM S-3
REGISTRATION STATEMENT UNDER
THE SECURITIES ACT OF 1933

TC PipeLines, LP
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction of incorporation or organization)		   52-2135448
(I.R.S. Employer Identification Number)

110 Turnpike Road, Suite 203
Westborough, Massachusetts 01581
(508) 871-7046
(Address, including zip code, and
telephone number, including area code,
of registrant's principal executive offices)		   Ronald J. Turner
TC PipeLines, LP
110 Turnpike Road, Suite 203
Westborough, Massachusetts 01581
(508) 871-7046
(Name, address, including zip code, and telephone number,
including area code, of agent for service)

With a copy to:

Andrews Kurth LLP
600 Travis, Suite 4200
Houston, Texas 77002
(713) 220-4200
Attn: Gislar Donnenberg
                     

       Approximate date of commencement of proposed sale to the public: From time to time after this registration statement becomes effective.

       If the only securities being registered on this Form are to be offered pursuant to dividend or interest reinvestment plans, please check the following box. o

       If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ý

       If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

       If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

       If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box. o

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be
Registered and Sold by the Registrant
and the Selling Unitholders

   Amount to be
Registered
   Proposed
Maximum Offering
Price per Unit
   Proposed
Maximum Aggregate
Offering Price(1)
   Amount of Registration Fee(2)
Primary Offering:                
  Common Units representing limited partner interests(3)                
  Debt Securities(4)                
  Total for sale by registrant(5)           $250,000,000   $29,425
Secondary Offering:(6)                
  Common Units representing limited partner interests   5,609,306   $37.65(7)   $211,190,371   $24,857.12
Total               $54,282.12(8)
(1)
Rule 457(o) under the Securities Act of 1933 permits the registration fee to be calculated on the basis of the maximum offering price of all the securities listed, and therefore, with respect to the securities offered by the registrant, the table does not specify information as to the amount of each class of security to be registered or the proposed maximum offering price per security.

(2)
The registration fee has been calculated pursuant to Rule 457(o) under the Securities Act of 1933 with respect to the securities offered by the registrant and pursuant to Rule 457(c) under the Securities Act of 1933 with respect to the Common Units offered by the selling unitholders based on the average of the high and low sales prices of Common Units on the Nasdaq Stock Market on December 20, 2004.

(3)
Subject to Note 5 below, an indeterminate amount of Common Units as may be sold from time to time by the registrant is being registered hereunder.

(4)
Subject to Note 5 below, an indeterminate principal amount of Debt Securities as may be sold from time to time by the registrant is being registered hereunder.

(5)
In no event will the aggregate offering price of all securities issued by the registrant from time to time pursuant to this Registration Statement exceed $250,000,000.

(6)
Up to 5,609,306 Common Units may be sold from time to time pursuant to this Registration Statement by the selling unitholders.

(7)
Estimated solely for the purpose of determining the registration fee on the basis of the average high and low sales prices of Common Units on the Nasdaq Stock Market on December 20, 2004.

(8)
Pursuant to Rule 457(p) under the Securities Act of 1933, the registrant hereby offsets the registration fee required in connection with this Registration Statement by $18,400 previously paid by the registrant in respect of $200,000,000 of unsold securities registered pursuant to the Registration Statement on Form S-3 (Registration No. 333-86804) filed with the Securities and Exchange Commission on April 23, 2002. Accordingly, pursuant to Rule 457(p), the total filing fee paid herewith is $35,882.12.

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete, and we may change it. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not printed.

Subject to completion, dated December 22, 2004

Prospectus

$250,000,000

TC PipeLines, LP

Common Units
Debt Securities

5,609,306
Common Units
Offered by Selling Unitholders

        TC PipeLines, LP may in one or more offerings offer and sell common units representing limited partner interests and debt securities. The aggregate initial offering price of the securities that we offer by this prospectus will not exceed $250,000,000. We will offer the securities in amounts, at prices and on terms to be determined by market conditions at the time of our offerings. We will provide the specific terms of the securities in supplements to this prospectus. The prospectus supplement may also add, update or change information contained in this prospectus.

        In addition, our general partner, TC PipeLines GP, Inc., may in one or more offerings offer and sell up to 2,809,306 common units and an affiliate of our general partner, TransCan Northern Ltd., may in one or more offerings offer and sell up to 2,800,000 common units, respectively, pursuant to arrangements made by each of TC PipeLines GP and TransCan Northern (the Selling Unitholders). The Selling Unitholders will offer the common units in amounts, at prices and on terms to be determined by market conditions at the time of their offerings. Unless otherwise provided in a prospectus supplement, we will not receive any of the proceeds from the sale of common units by the Selling Unitholders.

        You should read this prospectus and the applicable prospectus supplements carefully before you invest in any of our securities. This prospectus may not be used to consummate sales of our securities unless it is accompanied by a prospectus supplement.

        Our common units are quoted for trading on The Nasdaq Stock Market under the symbol "TCLP."

        See "Risk Factors" on page 5 to read about important risks that you should consider before buying our securities.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined whether this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is                        


TABLE OF CONTENTS

ABOUT THIS PROSPECTUS   1
WHERE YOU CAN FIND MORE INFORMATION   1
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS   2
ABOUT TC PIPELINES, LP   3
RISK FACTORS   5
  Risks Inherent in Our Business   5
  Risks Inherent in an Investment in TC PipeLines   9
  Tax Risks   12
USE OF PROCEEDS   14
RATIO OF EARNINGS TO FIXED CHARGES   14
DESCRIPTION OF COMMON UNITS   14
DESCRIPTION OF DEBT SECURITIES   15
  Specific Terms of each Series of Debt Securities in the Prospectus Supplement   15
  Provisions Only in the Senior Indenture   16
  Provisions Only in the Subordinated Indenture   20
  Consolidation, Merger or Asset Sale   20
  Modification of Indentures   20
  Events of Default and Remedies   21
  Registration of Notes   22
  Minimum Denominations   22
  No Personal Liability of General Partner   22
  Payment and Transfer   22
  Form, Exchange, Registration and Transfer   22
  Discharging Our Obligations   23
  Book Entry, Delivery and Form   23
  The Trustee   24
TAX CONSIDERATIONS   25
  Partnership Status   25
  Limited Partner Status   27
  Tax Consequences of Unit Ownership   27
  Tax Treatment of Operations   31
  Disposition of Common Units   32
  Uniformity of Common Units   34
  Tax-Exempt Organizations and Other Investors   35
  Administrative Matters   35
  State, Local and Other Tax Considerations   37
  Tax Consequences of Ownership of Debt Securities   38
INVESTMENT IN US BY EMPLOYEE BENEFIT PLANS   38
SELLING UNITHOLDERS   39
PLAN OF DISTRIBUTION   40
LEGAL   42
EXPERTS   42

        We have not authorized anyone to give any information or make any representation that differs from, or adds to, the information in this document or in our documents that are publicly filed with the Securities and Exchange Commission. Therefore, if anyone does give you different or additional information, you should not rely on it.

        If you are in a jurisdiction where it is unlawful to offer to exchange or sell, or to ask for offers to exchange or buy, the securities offered by this document, or if you are a person to whom it is unlawful to direct these activities, then the offer presented by this document does not extend to you.

        The information contained in this document speaks only as of its date unless the information specifically indicates that another date applies.


ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that we have filed with the Securities and Exchange Commission using a "shelf" registration process. Under this shelf registration process, we may sell up to $250,000,000 in total offering amount of the common units or debt securities described in this prospectus in one or more offerings. In addition, the Selling Unitholders may sell up to 5,609,306 of the common units described in this prospectus in one or more offerings. This prospectus generally describes us and the common units and debt securities. Each time we sell common units or debt securities with this prospectus, we will provide a prospectus supplement that will contain specific information about the terms of that offering and the securities offered in that offering. The prospectus supplement may also add to, update or change information in this prospectus. You should carefully read both this prospectus and any prospectus supplement and the additional information described under the heading "Where You Can Find More Information." As used in this prospectus, "we," "us," "our" and "TC PipeLines" mean TC PipeLines, LP and, where the context requires, include our subsidiary limited partnerships.


WHERE YOU CAN FIND MORE INFORMATION

        We have filed a registration statement with the SEC under the Securities Act of 1933 that registers the securities offered by this prospectus. The registration statement, including the attached exhibits, contains additional relevant information about us. The rules and regulations of the SEC allow us to omit some information included in the registration statement from this prospectus.

        In addition, we file annual, quarterly and other reports and other information with the SEC. You may read and copy any document we file at the SEC's public reference room at 450 Fifth Street, N.W., Washington, D.C. 20549 and at the SEC's regional offices at 233 Broadway, New York, New York, and at 500 West, Suite 1400, Madison Street, Chicago, Illinois 60661. Please call the SEC at 1-800-SEC-0330 for further information on their public reference rooms. Our SEC filings are also available at the SEC's web site at http://www.sec.gov. You can also obtain information about us at the offices of the Nasdaq Stock Market, 33 Whitehall Street, New York, New York, 10004.

        The SEC allows us to "incorporate by reference" the information we have filed with the SEC. This means that we can disclose important information to you without actually including the specific information in this prospectus by referring you to another document filed separately with the SEC. The information incorporated by reference is an important part of this prospectus. Information that we file later with the SEC will automatically update and may replace information in this prospectus and information previously filed with the SEC.

        We incorporate by reference the documents listed below that we have previously filed with the SEC. They contain important information about us and our financial condition.

        We also incorporate by reference additional documents that we may file with the SEC until all of the securities offered by this prospectus have been sold. These documents include periodic reports, such as Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K.

1


        You may obtain any of the documents incorporated by reference in this document through us or from the SEC through the SEC's website at the address provided above. Documents incorporated by reference are available from us without charge, excluding any exhibits to those documents unless the exhibit is specifically incorporated by reference in this document, by requesting them in writing or by telephone from us at the following address:

TC PipeLines, LP
110 Turnpike Road, Suite 203
Westborough, Massachusetts, 01581
Toll Free: (877) 290-2772
Direct Dial: (508) 871-7046


CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus, any accompanying prospectus supplement and the documents we have incorporated by reference contain forward-looking statements that relate to, among other things, anticipated financial performance, business prospects, strategies, market forces and commitments. Much of this information appears in "Management's Discussion and Analysis of Financial Condition and Results of Operations" which is incorporated by reference from our Annual Report on Form 10-K filed for the fiscal year ended December 31, 2003. The words "believe," "expect," "estimate" and "anticipate" and similar expressions identify forward-looking statements. Forward-looking statements include those that address activities, events or developments that we expect or anticipate may or will occur in the future.

        By its nature, such forward-looking information is subject to various risks and uncertainties that could cause our actual results and experience to differ materially from the anticipated results or other expectations expressed. For a detailed discussion of these risks and uncertainties, please read "Risk Factors" beginning on page 5 of this prospectus.

2


ABOUT TC PIPELINES, LP

        We are a publicly traded Delaware limited partnership formed in 1998 to acquire, own and participate in the management of United States based pipeline assets. TC PipeLines GP, Inc., an indirect wholly owned subsidiary of TransCanada Corporation, is our general partner and manages our operations. We own a 30% general partner interest in Northern Border Pipeline Company and a 49% general partner interest in Tuscarora Gas Transmission Company.

        Northern Border Pipeline Company.    In May of 1999, in connection with our initial public offering, we acquired a 30% general partner interest in Northern Border Pipeline Company from subsidiaries of TransCanada. The remaining 70% general partner interest in Northern Border Pipeline is held by Northern Border Partners, L.P., a publicly traded limited partnership. TransCanada, the indirect owner of TC PipeLines' general partner, is also the indirect owner of 17.5% of the general partner interest in Northern Border Partners, which entitles it to 12.25% of the voting power of Northern Border Pipeline. The remaining 82.5% of the general partner interest in Northern Border Partners is held by ONEOK, Inc. through Northern Plains Natural Gas Company and its wholly owned subsidiary, Pan Border Gas Company. As a result, ONEOK controls 57.75% of the management committee of Northern Border Pipeline Company. TransCanada and TC PipeLines collectively control 42.25% of the Northern Border Pipeline management committee.

        Northern Border Pipeline Company owns and manages a 1,249-mile regulated natural gas pipeline system that transports natural gas from the Canadian border at Port of Morgan, Montana to markets in the midwestern United States and connects with multiple pipelines, which allow shippers to access the various natural gas markets served by those pipelines.

        Tuscarora Gas Transmission Company. On September 1, 2000, we acquired a 49% general partner and voting interest in Tuscarora Gas Transmission Company from a subsidiary of TransCanada. Sierra Pacific Resources Company indirectly holds a 50% general partner and voting interest and TransCanada holds a 1% general partner and voting interest in Tuscarora.

        Tuscarora owns a 240-mile, 20-inch diameter, United States interstate pipeline system that originates at an interconnection point with facilities owned by Gas Transmission Northwest near Malin, Oregon and runs southeast through northeastern California and northwestern Nevada. Deliveries are also made directly to the local gas distribution system of Sierra Pacific.

        Our address is 110 Turnpike Road, Suite 203, Westborough, Massachusetts, 01581 and our telephone number at this address is (508) 871-7046.

3


Ownership Chart

        The following chart shows our organization, our ownership structure and our interests in Northern Border Pipeline and Tuscarora as of the date of this prospectus. The ownership percentages referred to in this prospectus reflect the approximate ownership interest in us and our subsidiary limited partnerships on a combined basis. The 31.41% limited partner interest shown in the chart includes 2,809,306 common units held in us by our general partner and 2,800,000 common units held by TransCan Northern. These 5,609,306 common units held by TC PipeLines GP and TransCan Northern may be sold by the Selling Unitholders pursuant to this prospectus. If all of these units are sold, TransCanada will retain its indirect 2% general partner interest and will continue to direct and manage all activities of TC PipeLines.

CHART

(1)
Represents 17.5% of the aggregate 2% General Partner Interest in Northern Border Partners, L.P. The remaining 82.5% of the aggregate 2% General Partner Interest is controlled by ONEOK, Inc.

(2)
A 50% General Partner Interest is held by Sierra Pacific Resources, and the remaining 1% General Partner Interest is held indirectly by TransCanada through TCPL Tuscarora Ltd.

4


RISK FACTORS

        Limited partner interests are inherently different from the capital stock of a corporation. Before you invest in our securities you should consider carefully the following risk factors together with all of the other information included in this prospectus, any prospectus supplement and the documents we have incorporated by reference into this document.

        If any of the following risks were actually to occur, our business, financial condition or results of operations could be materially adversely affected. In that event, the trading price of our common units could decline and you could lose all or part of your investment.

Risks Inherent in Our Business

We are dependent on Northern Border Pipeline and Tuscarora and may not be able to generate sufficient cash from the distributions from each of Northern Border Pipeline and Tuscarora to enable us to pay the expected quarterly distribution on the TC PipeLines common units every quarter.

        While we have a significant ownership interest in each of Northern Border Pipeline and Tuscarora, we do not control or operate either of these entities. The actual amount of cash we will have available to distribute to our common unitholders will significantly depend upon numerous factors relating to each of Northern Border Pipeline's and Tuscarora's businesses, most of which are beyond our control and the control of our general partner, including:

        Other factors that affect the actual amount of cash that we will have available for distribution to our unitholders include the following:

Cash distributions are dependent primarily on our cash flow, financial reserves and working capital borrowings.

        Cash distributions are not dependent solely on our profitability, which is affected by non-cash items. Therefore, we may make cash distributions during periods when we record losses and may not make cash distributions during periods when we record profits.

Northern Border Pipeline's and Tuscarora's indebtedness may limit their ability to borrow additional funds, make distributions to us or capitalize on business opportunities.

        Northern Border Pipeline is prohibited from making cash distributions during an event of default under its debt instruments. Provisions in Northern Border Pipeline's debt instruments limit its ability to incur indebtedness and engage in specific transactions that could reduce its ability to capitalize on business

5


opportunities that arise in the course of its business. Similarly, Tuscarora is prohibited from making cash distributions during an event of default under its debt instruments. Under Tuscarora's debt instruments, Tuscarora has granted a security interest in certain of its transportation contracts, which is available to noteholders upon an event of default. Any future refinancing of Northern Border Partners' or Tuscarora's existing indebtedness or any new indebtedness could have similar or greater restrictions.

If we are unable to make acquisitions on economically and operationally acceptable terms, either from third parties or TransCanada, our future financial performance will be limited to our participation in Northern Border Pipeline and Tuscarora.

        We may not be able to:

        Future acquisitions may involve the expenditure of significant funds. Depending upon the nature, size and timing of future acquisitions, we may be required to obtain additional financing. Additional financing may not be available to us on acceptable terms.

        In addition, we may not be able to acquire any more of TransCanada's United States pipeline assets. Neither our partnership agreement nor any other agreement requires TransCanada to pursue a business strategy that favors us, and TransCanada is under no obligation to make available to us business opportunities that may be beneficial to us. TransCanada's future acquisitions may not provide acquisition opportunities to us or, if these opportunities arose, they may not be on terms attractive to us. Moreover, TransCanada is not obligated to offer to us any assets it acquires as part of any future acquisitions.

Majority control of the Northern Border Pipeline management committee by affiliates of ONEOK, Inc. may limit our ability to influence Northern Border Pipeline.

        We own a 30% general partner interest in Northern Border Pipeline. The remaining 70% general partner interest in Northern Border Pipeline is owned by Northern Border Partners, L.P., a publicly traded limited partnership, which is not affiliated with us. ONEOK controls 57.75% of the Northern Border Pipeline management committee. Except as to any matters requiring unanimity, such as significant expansions or extensions to the pipeline system, the acceptance of rate cases and changes to, or suspensions of, the cash distribution policy, management committee members designated by ONEOK have the power to approve a particular matter requiring a majority vote despite the fact that our representative may vote against the project or other matter. Conversely, with respect to any matter requiring a majority vote, management committee members designated by ONEOK may disapprove a particular matter despite the fact that our representative may vote in favor of that matter.

If the Federal Energy Regulatory Commission (FERC) requires that Northern Border Pipeline's or Tuscarora's tariff be changed, Northern Border Pipeline's or Tuscarora's respective cash flows may be adversely affected.

        Northern Border Pipeline and Tuscarora are subject to extensive regulation by the FERC. The FERC's regulatory authority is not limited to but extends to matters including:

6

        Given the extent of regulation by the FERC and potential changes to regulations, we cannot predict:


        Northern Border Pipeline's ability to file for an increase of its rates before November 2005 to recover increases in most types of costs has been substantially eliminated as a result of the settlement of its last rate case. Any future rate increases proposed by Northern Border Pipeline will be subject to FERC approval.

If Northern Border Pipeline or Tuscarora do not maintain or increase their respective rate bases by successfully completing FERC-approved projects, the amount of revenue attributable to the return on the rate base they collect from their shippers will decrease over time.

        The Northern Border and Tuscarora pipeline systems are generally allowed to collect from their customers a return on their assets or "rate base" as reflected in their financial records as well as recover that rate base through depreciation. The amount they may collect from customers decreases as the rate base declines as a result of, among other things, depreciation and amortization. In order to avoid a reduction in the level of cash available for distributions to its partners, based on its current FERC-approved tariff, each of these pipelines must maintain or increase its rate base through projects that maintain or add to existing pipeline facilities. These projects will depend upon many factors including:

        Northern Border Pipeline's and Tuscarora's ability to complete these projects is also subject to numerous business, economic, regulatory, competitive and political uncertainties beyond its control, and neither Northern Border Pipeline nor Tuscarora may be able to complete these projects.

If any significant shipper fails to perform its contractual obligations, Northern Border Pipeline's or Tuscarora's respective cash flows and financial condition could be adversely impacted.

        As of December 31, 2003, the three largest shippers on the Northern Border pipeline system accounted for approximately 49% of contracted capacity. Sierra Pacific Power, a wholly owned subsidiary of Sierra Pacific Resources, is Tuscarora's largest shipper, with firm contracts for approximately 68% of its capacity. Sierra Pacific Resources and Sierra Pacific Power have below-investment grade credit ratings. While TC PipeLines has no current indication that Sierra Pacific Power is unable to meet its ongoing contractual obligations, TC PipeLines is unable to predict the future financial condition of Sierra Pacific Power and its long-term ability to meet its obligations under existing agreements with Tuscarora. If any of the significant shippers on either Northern Border Pipeline or Tuscarora fail to meet their contractual obligations, our ability to make cash distributions to our unitholders at current levels may be adversely affected.

7


The long-term financial conditions of Northern Border Pipeline and Tuscarora, and as a result, of TC PipeLines, are dependent on the continued availability of western Canadian natural gas for import into the United States.

        The development of additional natural gas reserves requires significant capital expenditures by others for exploration and development drilling and the installation of production, gathering, storage, transportation and other facilities that permit natural gas to be produced and delivered to pipelines that interconnect with Northern Border's or Tuscarora's pipeline systems. Low prices for natural gas, regulatory limitations, or the lack of available capital for these projects could adversely affect the development of additional reserves and the production, gathering, storage, pipeline transmission, import and export of natural gas supplies. If the availability of western Canadian natural gas were to decline, existing shippers on the Northern Border and Tuscarora pipeline systems may be unlikely to extend their contracts and Northern Border Pipeline and Tuscarora may be unable to find replacement shippers for lost capacity. Furthermore, additional natural gas reserves may not be developed in commercial quantities and in sufficient amounts to fill the capacities of each of the Northern Border and Tuscarora pipeline systems.

Northern Border Pipeline's and Tuscarora's businesses depend in part on the level of demand for western Canadian natural gas in the markets the pipeline systems serve. If demand for western Canadian natural gas decreases, shippers may not enter into or renew contracts.

        Northern Border Pipeline's and Tuscarora's businesses depend in part on the level of demand for western Canadian natural gas in the markets the pipeline systems serve. The volumes of natural gas delivered to these markets from other sources affect the demand for both western Canadian natural gas and use of these pipeline systems. Demand for western Canadian natural gas also influences the ability and willingness of shippers to use the Northern Border and Tuscarora pipeline systems to meet the demand that these pipeline systems serve. If either of the Northern Border or Tuscarora pipeline systems are used less over the long term, we may have lower revenues and less cash to distribute to our unitholders.

Because of the highly competitive nature of the natural gas transmission business, Northern Border Pipeline and Tuscarora may not be able to maintain existing customers or acquire new customers when the current shipper contracts expire.

        Other pipeline systems that transport natural gas serve the same markets served by the Northern Border and Tuscarora pipeline systems. As a result, Northern Border Pipeline and Tuscarora face competition from other pipeline systems.

        Northern Border Pipeline may not be able to renew or replace expiring contracts. The renewal or replacement of existing contracts with customers of Northern Border Pipeline depends on a number of factors beyond Northern Border Pipeline's control, including:

        With contracts scheduled to expire through May 2005, approximately 800 MMcf/d or 30% of capacity will become available on the Northern Border Pipeline system from port of Morgan, Montana to the Venture, Iowa delivery point. Because the forward natural gas basis differentials between Western Canada and Northern Border Pipeline's market centers may be less than the total transportation cost at maximum tariff rates, Northern Border Pipeline may sell a significant portion of available capacity on a short-term basis. Additionally, if the forward natural gas basis differentials do not support maximum rates, Northern Border Pipeline's revenue may be adversely affected.

        Tuscarora competes in the northern Nevada natural gas transmission market with Paiute Pipeline Co., owned by Southwest Gas Co. of Las Vegas, Nevada. The Paiute pipeline interconnects with Northwest Pipeline Corp. at the Nevada-Idaho border and transports gas from British Columbia and the U.S. Rocky Mountain Basin to the northern Nevada market. As a result of competition from the Paiute pipeline,

8


Tuscarora's proposed 2005 expansion was canceled pursuant to the October 2004 settlement with the potential expansion shippers.

        TransCanada's main pipeline systems transport natural gas from the same natural gas reserves in western Canada that are used by Northern Border Pipeline's and Tuscarora's customers. TransCanada is not prohibited from actively competing with Northern Border Pipeline for the transport of western Canadian natural gas.

Northern Border Pipeline's and Tuscarora's operations are regulated by federal and state agencies responsible for environmental protection and operational safety.

        Risks of substantial costs and liabilities are inherent in pipeline operations and each of Northern Border Pipeline and Tuscarora may incur substantial costs and liabilities in the future as a result of stricter environmental and safety laws, regulations and enforcement policies and claims for personal or property damages resulting from Northern Border Pipeline's or Tuscarora's operations. If either Northern Border Pipeline or Tuscarora, as applicable, is not able to recover these costs, cash distributions to unitholders could be adversely affected.

        Northern Border Pipeline's and Tuscarora's operations are subject to operational hazards and unforeseen interruptions, including natural disasters, adverse weather, accidents or other events beyond their control. A casualty occurrence might result in a loss of equipment or life, as well as injury and extensive property or environmental damage.

Risks Inherent in an Investment in TC PipeLines

You will have limited voting rights and will not control our general partner.

        The general partner is our manager and operator. Unlike the holders of common stock in a corporation, holders of common units will have only limited voting rights on matters affecting our business. You will have no right to elect our general partner on an annual or other continuing basis. Our general partner may not be removed except by the vote of the holders of at least 662/3% of the outstanding units and upon the election of a successor general partner by the vote of the holders of a majority of the outstanding common units. These required votes would include the votes of units owned by our general partner and its affiliates. The ownership of an aggregate of approximately 32% of the outstanding units by our general partner and its affiliates has the practical effect of making removal of our general partner difficult.

        In addition, the partnership agreement contains some provisions that may have the effect of discouraging a person or group from attempting to remove our general partner or otherwise change our management. If our general partner is removed as our general partner under circumstances where cause does not exist and units held by our general partner and its affiliates are not voted in favor of that removal:

        These provisions may diminish the price at which the common units will trade under some circumstances.

        The partnership agreement also contains provisions limiting the ability of unitholders to call meetings of unitholders or to acquire information about our operations, as well as other provisions limiting the unitholders' ability to influence the manner or direction of management. Further, if any person or group other than our general partner or its affiliates or a direct transferee of our general partner or its affiliates acquires beneficial ownership of 20% or more of any class of units then outstanding, that person or group will lose voting rights with respect to all of its units. As a result, you will have limited influence on matters affecting our operations, and third parties may find it difficult to attempt to gain control of us, or influence our activities.

9


We may issue additional common units without unitholder approval, which would dilute existing unitholders' interest.

        Our general partner can cause us to issue additional common units, without the approval of unitholders, in the following circumstances:

        In addition, we may issue an unlimited number of limited partner interests of any type without the approval of the unitholders. Based on the circumstances of each case, the issuance of additional common units or securities ranking senior to or on a parity with the common units may dilute the value of the interests of the then-existing holders of common units in the net assets of TC PipeLines and dilute the interests of unitholders in distributions by TC PipeLines. Our partnership agreement does not give the unitholders the right to approve the issuance by us of equity securities ranking junior to the common units at any time.

Issuance of additional common units will increase the risk that we will be unable to pay the full minimum quarterly distribution on all common units.

        Our ability to pay the full minimum quarterly distribution on all the common units may be reduced by any increase in the number of outstanding common units. Additional common units would be issued:

        Any of these actions will increase the percentage of the aggregate minimum quarterly distribution payable to the common unitholders, which will in turn have the effect of increasing the risk that we will be unable to pay the minimum quarterly distribution in full on all the common units.

Cost reimbursements due to our general partner may be substantial and could reduce our cash available for distribution.

        Prior to making any distribution on the common units, we will reimburse our general partner and its affiliates, including officers and directors of the general partner, for all expenses incurred by our general partner and its affiliates on our behalf. During the year ended December 31, 2003, and during the nine-month period ended September 30, 2004, we paid fees and reimbursements to our general partner in the amounts of $0.7 and $0.6 million, respectively. Our general partner in its sole discretion will determine the amount of these expenses. In addition, our general partner and its affiliates may provide us services for which we will be charged reasonable fees as determined by the general partner. The reimbursement of expenses and the payment of fees could adversely affect our ability to make distributions.

Our general partner has a limited call right that may require unitholders to sell their common units at an undesirable time or price.

        If our general partner and its affiliates who currently own approximately 32% of our common units come to own 80% or more of the common units, the general partner will have the right, which it may assign to any of its affiliates or us, to acquire all, but not less than all, of the remaining common units held by unaffiliated persons at a price generally equal to the then-current market price of the common units. As a consequence, you may be required to sell your common units at a time when you may not desire to sell them or at a price that is less than the price you would desire to receive upon sale. You may also incur a tax liability upon a sale of your units.

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Unitholders may not have limited liability in some circumstances.

        The limitations on the liability of holders of limited partner interests for the obligations of a limited partnership have not been clearly established in some states. If it were to be determined that:

then you could be held liable in some circumstances for TC PipeLines' obligations to the same extent as a general partner. In addition, under some circumstances a unitholder may be liable to TC PipeLines for the amount of a distribution for a period of three years from the date of the distribution.

Without the consent of each unitholder, Northern Border Pipeline or Tuscarora might be converted into a corporation, which would result in Northern Border Pipeline or Tuscarora, as the case may be, being subject to corporate income taxes.

        If it becomes unlawful to conduct the business of Northern Border Pipeline or Tuscarora as a partnership and some other conditions are satisfied, the business and assets of Northern Border Pipeline or Tuscarora, as the case may be, will automatically be transferred to a corporation without the vote or consent of unitholders. Therefore, you would not receive a proxy or consent solicitation statement in connection with that transaction. However, we believe that it is unlikely that circumstances requiring an automatic transfer will occur. A transfer to corporate form would result in Northern Border Pipeline or Tuscarora being subject to corporate income taxes and would likely be materially adverse to its, and, therefore, our, results of operations and financial condition.

If we were to be found to be an "investment company" under the Investment Company Act of 1940, our contracts may be voidable and our offers of securities may be subject to rescission.

        If we were deemed to be an unregistered "investment company" under the Investment Company Act, our contracts may be voidable and our offers of securities may be subject to rescission, and we may also be subject to other materially adverse consequences.

        Our sole assets consist of a 30% general partner interest in Northern Border Pipeline and 49% general partner interest in Tuscarora. We could be deemed to be an "investment company" under the Investment Company Act if these general partner interests constituted an "investment security", as defined in the Investment Company Act. If we were deemed to be an "investment company", then we would be required to be registered as an investment company under the Investment Company Act. In that case, there would be a substantial risk that we would be in violation of the Investment Company Act because of the practical inability to register under the Investment Company Act.

If we were to lose TransCanada's management expertise, we would not have sufficient stand-alone resources to operate.

        We do not presently have sufficient stand-alone management resources to operate without services provided by TransCanada. Further, we would not be able to evaluate potential acquisitions and successfully complete acquisitions without TransCanada's resources.

Our credit facilities may limit our ability to borrow additional funds or capitalize on business opportunities.

        Our credit facilities contain restrictive covenants that may prevent us from engaging in certain transactions that we deem beneficial. These agreements require us to comply with various affirmative and negative covenants including restrictions on:

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        In addition, our third party credit facility requires us to maintain certain financial ratios and contains restrictions on:

        The instruments governing any future debt may contain similar restrictions.

Tax Risks

        For a general discussion of expected material federal income tax consequences of owning and disposing of common units or debt securities, please read "Tax Considerations".

The IRS could treat us as a corporation, which would substantially reduce the cash available for distribution to unitholders.

        The anticipated after-tax benefit of an investment in us depends largely on our classification as a partnership for federal income tax purposes. We have not requested, and do not plan to request, a ruling from the IRS on this or any other matter affecting us.

        If we were treated as a corporation for federal income tax purposes, we would pay federal income tax on our income at the corporate tax rate, which is currently a maximum of 35%, distributions would generally be taxed again to you as corporate distributions, and no income, gains, losses, deductions or credits would flow through to you. Because a tax would be imposed upon us as an entity, the cash available for distribution to you would be substantially reduced. Our treatment as a corporation would result in a material reduction in the anticipated cash flow and after-tax return to you and thus would likely result in a substantial reduction in the value of the common units.

        Current law may change so as to cause us to be taxable as a corporation for federal income tax purposes or otherwise to be subject to entity-level taxation. Our partnership agreement provides that, if a law is enacted or existing law is modified or interpreted in a manner that subjects us to taxation as a corporation or otherwise subjects us to entity-level taxation for federal, state or local income tax purposes, then specified provisions of the partnership agreement relating to distributions will be subject to change. These changes would include a decrease in distributions to reflect the impact of that law on us.

We have not requested an IRS ruling with respect to our tax treatment.

        We have not requested a ruling from the IRS with respect to any matter affecting us. The IRS may adopt positions that differ from our counsel's conclusions expressed in this prospectus or from the positions we take. It may be necessary to resort to administrative or court proceedings in an effort to sustain some or all of our counsel's conclusions or the positions we take. Any contest with the IRS may materially and adversely impact the market for the common units and the price at which the common units trade. In addition, the costs of any contest with the IRS will be borne directly or indirectly by some or all of the unitholders and the general partner.

You may be required to pay taxes on income from us even if you receive no cash distributions.

        You will be required to pay federal income taxes and, in some cases, state and local income taxes on your allocable share of our income, whether or not you receive cash distributions from us. You may not receive cash distributions equal to your allocable share of our taxable income or even the tax liability that results from that income.

Tax gain or loss on the disposition of common units could be different than expected.

        If you sell your common units, you will recognize gain or loss equal to the difference between the amount realized and your tax basis in those common units. Prior distributions in excess of the total net taxable income you were allocated for a common unit which decreased your tax basis in that common unit will, in effect, become taxable income if the common unit is sold at a price greater than your tax basis in that common unit, even if the price is less than your original cost. A substantial portion of the amount realized, whether or not representing gain, may be ordinary income to you. If the IRS successfully contests

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some conventions we use, you could recognize more gain on the sale of common units than would be the case under those conventions without the benefit of decreased income in prior years.

Investors other than individuals that are U.S. residents may have adverse tax consequences from owning common units.

        Investment in common units by tax-exempt entities, regulated investment companies and foreign persons raises issues unique to these persons. For example, virtually all of our income allocated to organizations exempt from federal income tax, including individual retirement accounts and other retirement plans, will be unrelated business taxable income and will be taxable to them. Recent legislation treats net income derived from the ownership of certain publicly traded partnerships as qualifying income to a regulated investment company. However, this legislation is only effective for taxable years beginning after October 22, 2004, the date of enactment. For taxable years beginning prior to the date of enactment, very little of our income will be qualifying income to a regulated investment company. Distributions to foreign persons will be reduced by withholding taxes. Foreign persons will be required to file federal income tax returns and pay tax on their share of our taxable income.

We have registered as a "tax shelter." This may increase the risk of an IRS audit of TC PipeLines or a unitholder.

        We have registered as a "tax shelter" with the Secretary of the Treasury. Prior to enactment of recent legislation, the IRS required that some types of entities, including some partnerships, register as "tax shelters" in response to the perception that they claim tax benefits that the IRS may believe to be unwarranted. As a result, we may be audited by the IRS and tax adjustments could be made. Any unitholder owning less than a 1% interest in us has a very limited right to participate in the income tax audit process. Further, any adjustments in our tax returns will lead to adjustments in your tax returns and may lead to audits of your tax returns and adjustments of items unrelated to us. You would bear the cost of any expenses incurred in connection with an examination of your personal tax return.

We treat a purchaser of common units as having the same tax benefits as the seller. A successful IRS challenge could adversely affect the value of the common units.

        Because we cannot match transferors and transferees of common units, we have adopted depreciation and amortization conventions that do not conform to all aspects of specified Treasury regulations. A successful challenge to those conventions by the IRS could adversely affect the amount of tax benefits available to you or could affect the timing of tax benefits or the amount of gain from your sale of common units and could have a negative impact on the value of the common units or result in audit adjustments to your tax returns.

The sale or exchange of 50% or more of our capital and profits interests will result in the termination of our partnership for federal income tax purposes.

        We will be considered to have terminated for federal income tax purposes if there is a sale or exchange of 50% or more of the total interests in our capital and profits within a 12-month period. Our termination would, among other things, result in the closing of our taxable year for all unitholders and could result in a deferral of depreciation deductions allowable in computing our taxable income. Please read "Tax Considerations — Disposition of Common Units — Constructive Termination" for a discussion of the consequences of our termination for federal income tax purposes.

You will likely be subject to state and local taxes as a result of an investment in units.

        In addition to federal income taxes, you will likely be subject to other taxes, including state and local taxes, unincorporated business taxes and estate, inheritance or intangible taxes that are imposed by the various jurisdictions in which we do business or own property. You may be required to file state and local income tax returns and pay state and local income taxes in some or all of the jurisdictions in which we do business or own property and may be subject to penalties for failure to comply with those requirements. It is your responsibility to file all required United States federal, state and local tax returns. Counsel has not rendered an opinion on the state or local tax consequences of an investment in us.

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USE OF PROCEEDS

        Except as otherwise provided in the applicable prospectus supplement, we will use the net proceeds we receive from the sale of securities for general purposes, repayment of debt, capital expenditures, future acquisitions and working capital.

        Unless otherwise provided in a prospectus supplement, we will not receive any proceeds from the sale of our common units by the Selling Unitholders.


RATIO OF EARNINGS TO FIXED CHARGES

        The ratio of earnings to fixed charges for each of the periods indicated is as follows:

 
   May 28 -
December 31, 1999
   Year Ended December 31, 2000
   Year Ended December 31, 2001
   Year Ended December 31, 2002
   Year Ended December 31, 2003
   Nine Months
Ended
September 30, 2004
Ratio of Earnings to Fixed Charges   N/A(1)   68.34x   39.34x   107.91x   240.55x   110.56x
(1)
On May 28, 1999, we acquired a 30% interest in Northern Border Pipeline. Prior to that date, we had no operations. We did not incur interest expense during the period May 28, 1999 to December 31, 1999.

        For purposes of calculating the ratio of earnings to fixed charges:


DESCRIPTION OF COMMON UNITS

Number Of Units

        We currently have 17,500,000 common units outstanding, of which 11,890,694 are held by the public and 5,609,306 are held by the Selling Unitholders. The common units represent an aggregate 98% limited partner interest and the general partner interest represents an aggregate 2% general partner interest in the partnership.

        Under our partnership agreement we may issue, without further unitholder action, an unlimited number of additional limited partner interests and other equity securities with such rights, preferences and privileges as may be established by the general partner in its sole discretion.

Distributions

        In general, the general partner is entitled to 2% of all cash distributions and the unitholders are entitled to the remaining 98% of all cash distributions. We will make quarterly cash distributions to our partners comprising all of our Available Cash. Available Cash is defined in the partnership agreement and generally means, with respect to any quarter of the partnership, all cash on hand at the end of such quarter less the amount of cash reserves that is necessary or appropriate in the reasonable discretion of the general partner to:

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        We distribute Available Cash from our operations in the following manner:

Voting

        Each holder of common units is entitled to one vote for each common unit on all matters submitted to a vote of the unitholders; provided that, if at any time any person or group owns beneficially 20% or more of all common units, such common units so owned may not be voted on any matter and may not be considered to be outstanding when sending notices of a meeting of unitholders (unless otherwise required by law), calculating required votes, determining the presence of a quorum or for other similar purposes under our partnership agreement.

Listing

        Our outstanding common units are listed on the Nasdaq Stock Market under the symbol "TCLP." Any additional common units we issue will also be listed on Nasdaq.

Transfer Agent And Registrar

        Our transfer agent and registrar for the common units is Mellon Investor Services, LLC.


DESCRIPTION OF DEBT SECURITIES

        The following description sets forth the general terms and provisions that could apply to the debt securities. Each prospectus supplement will state the particular terms that actually will apply to the debt securities included in the supplement.

        The debt securities will be either our senior debt securities or our subordinated securities. We do not have any debt securities outstanding at this time.

        In addition to the following summary, you should refer to the applicable provisions of the senior indenture and the subordinated indenture for more detailed information. We have filed forms of each of the senior indenture and the subordinated indenture as exhibits to the registration statement of which this prospectus is a part. The final indentures and the applicable supplemental indentures will be filed as exhibits to a Current Report on Form 8-K in connection with a particular offering.

        Neither indenture limits the aggregate principal amount of debt securities that we may issue under that indenture. The debt securities may be issued in one or more series as we may authorize at various times. All debt securities will be unsecured. The senior securities will have the same rank as all of our other unsecured and unsubordinated debt. The subordinated securities will be subordinated to senior indebtedness as described under "Provisions Only in the Subordinated Indenture — Subordinated Debt Securities Subordinated to Senior Debt" below.

Specific Terms of each Series of Debt Securities in the Prospectus Supplement

        A prospectus supplement and a supplemental indenture relating to any series of debt securities being offered will include specific terms relating to such debt securities. These terms will include some or all of the following:

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Provisions Only in the Senior Indenture

        The senior debt securities will rank equally in right of payment with all of our other senior and unsubordinated debt and senior in right of payment to any of our subordinated debt (including the subordinated debt securities). The senior indenture may contain restrictive covenants, including provisions that:

        The subordinated indenture may not contain any similar provisions. We have described below these provisions and some of the defined terms used in them.

Limitation on Liens

        The Senior Indenture may provide that we will not, nor will we permit any Subsidiary to, create, assume, incur or suffer to exist any lien upon any property or assets, whether owned or leased on the date of the Senior Indenture or thereafter acquired, to secure any debt of TC PipeLines or any other person (other than the senior debt securities issued thereunder), without in any such case making effective provision whereby all of the senior debt securities outstanding thereunder shall be secured equally and ratably with, or prior to, such debt so long as such debt shall be so secured.

        This restriction does not apply to:

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        Notwithstanding the foregoing, under the Senior Indenture, we may, and may permit any Subsidiary to, create, assume, incur, or suffer to exist any lien upon any property or assets to secure debt of TC PipeLines or any person (other than the senior debt securities) that is not excepted by clauses (1) through (12), inclusive, above without securing the senior debt securities issued under the Senior Indenture, provided that the aggregate principal amount of all debt then outstanding secured by such lien and all similar liens, together with all net sale proceeds from Sale-Leaseback Transactions (excluding Sale-Leaseback Transactions permitted by clauses (1) through (4), inclusive, of the first paragraph of the Restriction on Sale-Leasebacks covenant described below) does not exceed 15% of Consolidated Net Tangible Assets (as defined below).

        "Non-Recourse Debt" means:

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        provided that the recourse of the lender thereof or any agent, trustee, receiver or other person acting on behalf of the lender in respect of such debt or any judgment in respect thereof is limited in all circumstances (other than in respect of false or misleading representations or warranties and customary indemnities provided with respect to such financings) to the assets created, developed, constructed, or acquired with respect to which such debt has been incurred or assumed and to any receivables, inventory, equipment, chattel paper, intangibles and other rights or collateral arising from or connected with the assets created, developed, constructed or acquired (and, for certainty, shall include the shares or other ownership interests of a single purpose entity (or any parent thereof) which holds only such assets and other rights and collateral arising from or connected therewith) and to which the lender has recourse.

        "Permitted Liens" means:

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        "Consolidated Net Tangible Assets" means, at any date of determination, the total amount of assets after deducting therefrom:

Restrictions on Sale-Leasebacks

        The Senior Indenture may provide that we will not, and will not permit any Subsidiary to, engage in the sale or transfer by TC PipeLines or any Subsidiary of any property or assets to a person (other than TC PipeLines or a Subsidiary) and the taking back by TC PipeLines or any Subsidiary, as the case may be, of a lease of such property or assets (a "Sale-Leaseback Transaction"), unless:

        "Pari Passu Debt" means any debt of TC PipeLines, whether outstanding on the date any securities are issued under the Indenture or thereafter created, incurred or assumed, unless in the case of any particular debt, the instrument creating or evidencing the same or pursuant to which the same is outstanding expressly provides that such debt shall be subordinated in right of payment to the securities.

        Notwithstanding the foregoing, TC PipeLines may, and may permit any of its Subsidiaries to, effect any Sale-Leaseback Transaction that is not excepted by clauses (1) through (4) above; provided that the net sale proceeds from such Sale-Leaseback Transaction, together with the aggregate principal amount of then outstanding debt (other than the senior debt securities) secured by liens upon any property or assets of TC PipeLines or its Subsidiaries not excepted by clauses (1) through (12) of the second paragraph of the limitation on liens covenant described above, do not exceed 15% of the Consolidated Net Tangible Assets.

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Provisions Only in the Subordinated Indenture

Subordinated Debt Securities Subordinated to Senior Debt

        The subordinated debt securities will rank junior in right of payment to all of our Senior Debt. "Senior Debt" is defined to include all notes or other evidences of indebtedness, including our guarantees for money we borrowed, not expressed to be subordinate or junior in right of payment to any other of our indebtedness.

Payment Blockages

        The subordinated indenture may provide that no payment of principal, interest or any premium on the subordinated debt securities may be made in the event that we fail to pay when due any amounts on any Senior Debt and in other instances specified in the indenture.

No Limitation on Amount of Senior Debt

        The subordinated indenture will not limit the amount of Senior Debt that we may incur.

Consolidation, Merger or Asset Sale

        We may not consolidate with or merge into any other entity or sell, lease or transfer our properties and assets as, or substantially as, an entirety to, any entity, unless:

Modification of Indentures

        We may modify or amend each Indenture if the holders of a majority in principal amount of the outstanding debt securities of all series issued under the Indenture affected by the modification or amendment consent to it. Without the consent of each outstanding debt security affected, however, no modification may:

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        We may modify or amend the Indenture without the consent of any holders of the debt securities in certain circumstances or for certain purposes, including:

        The holders of a majority in principal amount of the outstanding debt securities of any series may waive past defaults under the Indenture and compliance by us with our covenants with respect to the debt securities of that series only. Those holders may not, however, waive any default in any payment on any debt security of that series or compliance with a provision that cannot be modified or amended without the consent of each holder affected.

Events of Default and Remedies

        "Event of Default" when used in an Indenture, may mean any of the following:

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        The subordination does not affect our obligation, which is absolute and unconditional, to pay, when due, the principal of and any premium and interest on the subordinated debt securities. In addition, the subordination does not prevent the occurrence of any default under the subordinated indenture.

        An Event of Default for a particular series of debt securities does not necessarily constitute an Event of Default for any other series of debt securities issued under an Indenture. The Trustee may withhold notice to the holders of debt securities of any default (except in the payment of principal or interest) if it considers such withholding of notice to be in the best interests of the holders.

        If an Event of Default for any series of debt securities occurs and continues, the Trustee or the holders of at least 25% in aggregate principal amount of the debt securities of the series may declare the entire principal of all the debt securities of that series to be due and payable immediately. If this happens, subject to certain conditions, the holders of a majority of the aggregate principal amount of the debt securities of that series can void the declaration.

        Other than its duties in case of a default, a Trustee is not obligated to exercise any of its rights or powers under any Indenture at the request, order or direction of any holders, unless the holders offer the Trustee reasonable indemnity. If they provide this reasonable indemnification, the holders of a majority in principal amount of any series of debt securities may direct the time, method and place of conducting any proceeding or any remedy available to the Trustee, or exercising any power conferred upon the Trustee, for any series of debt securities.

Registration of Notes

        We may issue debt securities of a series in registered, bearer, coupon or global form.

Minimum Denominations

        Unless the prospectus supplement for each issuance of debt securities states otherwise the securities will be issued in registered form in amounts of $1,000 each or multiples of $1,000.

No Personal Liability of General Partner

        Unless otherwise stated in a prospectus supplement and supplemental indenture relating to a series of debt securities being offered, the General Partner and its directors, officers, employees and shareholders will not have any liability for our obligations under the Indentures or the debt securities. Each holder of debt securities by accepting a debt security waives and releases all such liability. The waiver and release are part of the consideration for the issuance of the debt securities.

Payment and Transfer

        Principal, interest and any premium on fully registered securities will be paid at designated places. Payment will be made by check mailed to the persons in whose names the debt securities are registered on days specified in the Indentures or any prospectus supplement. Debt securities payments in other forms will be paid at a place designated by us and specified in a prospectus supplement.

        Fully registered securities may be transferred or exchanged at the corporate trust office of the Trustee or at any other office or agency maintained by us for such purposes, without the payment of any service charge except for any tax or governmental charge.

Form, Exchange, Registration and Transfer

        Debt securities of any series will be exchangeable for other debt securities of the same series, the same total principal amount and the same terms but in different authorized denominations in accordance with the Indenture. Holders may present debt securities for registration of transfer at the office of the security registrar or any transfer agent we designate. The security registrar or transfer agent will effect the transfer or exchange when it is satisfied with the documents of title and identity of the person making the request. We will not charge a service charge for any registration of transfer or exchange of the debt securities. We may, however, require the payment of any tax or other governmental charge payable for that registration.

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        We will appoint the trustee under each Indenture as security registrar for the debt securities issued under that Indenture. We are required to maintain an office or agency for transfers and exchanges in each place of payment. We may at any time designate additional transfer agents for any series of debt securities. In the case of any redemption in part, we will not be required:

Discharging Our Obligations

        We may choose to either discharge our obligations on the debt securities of any series in a legal defeasance, or to release ourselves from our covenant restrictions on the debt securities of any series in a covenant defeasance. We may do so at any time on the 91st day after we deposit with the Trustee sufficient cash or government securities to pay the principal, interest, any premium and any other sums due to the stated maturity date or a redemption date of the debt securities of the series. If we choose the legal defeasance option, the holders of the debt securities of the series will not be entitled to the benefits of the Indenture except for registration of transfer and exchange of debt securities, replacement of lost, stolen or mutilated debt securities, conversion or exchange of debt securities, sinking fund payments and receipt of principal and interest on the original stated due dates or specified redemption dates. We may discharge our obligations under the Indentures or release ourselves from covenant restrictions only if we meet certain requirements. Among other things, we must deliver an opinion of our legal counsel that the discharge will not result in holders of debt securities having to recognize taxable income or loss or subject then to different tax treatment. In the case of legal defeasance, this opinion must be based on either an IRS letter ruling or change in federal tax law. We may not have a default on the debt securities discharged on the date of deposit. The discharge may not violate any of our agreements. The discharge may not result in our becoming an investment company in violation of the Investment Company Act of 1940.

Book Entry, Delivery and Form

        The debt securities of a series may be issued in whole or in part in the form of one or more global certificates that will be deposited with a depositary identified in a prospectus supplement.

        Unless otherwise stated in any prospectus supplement, The Depository Trust Company, (DTC) will act as depositary. Book-entry notes of a series will be issued in the form of a global note that will be deposited with DTC. This means that we will not issue certificates to each holder. One global note will be issued to DTC who will keep a computerized record of its participants (for example, your broker) whose clients have purchased the notes. The participant will then keep a record of its clients who purchased the notes. Unless it is exchanged in whole or in part for a certificate note, a global note may not be transferred; except that DTC, its nominees and their successors may transfer a global note as a whole to one another.

        Beneficial interests in global notes will be shown on, and transfers of global notes will be made only through, records maintained by DTC and its participants.

        DTC has provided us with the following information: DTC is a limited-purpose trust company organized under the New York Banking Law, a "banking organization" within the meaning of the New York Banking Law, a member of the United States Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code and a "clearing agency" registered under the provisions of Section 17A of the Exchange Act. DTC holds securities that its participants ("Direct Participants") deposit with DTC. DTC also records the settlement among Direct Participants of securities transactions, such as transfers and pledges, in deposited securities through computerized records for Direct Participants' accounts. This eliminates the need to exchange certificates. Direct Participants include securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations.

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        DTC's book-entry system is also used by other organizations such as securities brokers and dealers, banks and trust companies that work through a Direct Participant. The rules that apply to DTC and its participants are on file with the SEC.

        DTC is owned by a number of its Direct Participants and by the New York Stock Exchange, Inc., The American Stock Exchange, Inc. and the National Association of Securities Dealers, Inc.

        We will wire principal and interest payments to DTC's nominee. We and the Trustee will treat DTC's nominee as the owner of the global notes for all purposes. Accordingly, we, the Trustee and any paying agent will have no direct responsibility or liability to pay amounts due on the global notes to owners of beneficial interests in the global notes.

        It is DTC's current practice, upon receipt of any payment of principal or interest, to credit Direct Participants' accounts on the payment date according to their respective holdings of beneficial interests in the global notes as shown on DTC's records. In addition, it is DTC's current practice to assign any consenting or voting rights to Direct Participants whose accounts are credited with notes on a record date, by using an omnibus proxy. Payments by participants to owners of beneficial interests in the global notes, and voting by participants, will be governed by the customary practices between the participants and owners of beneficial interests, as is the case with notes held for the account of customers registered in "street name." However, payments will be the responsibility of the participants and not of DTC, the Trustee or us.

        Debt Securities represented by a global note will be exchangeable for certificated notes with the same terms in authorized denominations only if:

The Trustee

Resignation or Removal of Trustee

        Under provisions of the Indentures and the Trust Indenture Act of 1939, as amended, governing trustee conflicts of interest, any uncured Event of Default with respect to any series of senior debt securities will force the trustee to resign as trustee under either the Subordinated Indenture or the Senior Indenture. Also, any uncured Event of Default with respect to any series of subordinated debt securities will force the trustee to resign as trustee under either the Senior Indenture or the Subordinated Indenture. Any resignation will require the appointment of a successor trustee under the applicable Indenture in accordance with the terms and conditions of such Indenture. We may appoint a separate trustee for any series of debt securities. We use the term "Trustee" to refer to the trustee appointed with respect to any such series of debt securities. The holders of a majority in aggregate principal amount of the debt securities of any series may remove the Trustee with respect to the debt securities of such series.

Limitations on Trustee if it is a Creditor of TC PipeLines

        Each Indenture may contain certain limitations on the right of the Trustee thereunder, in the event that it becomes a creditor of TC PipeLines, to obtain payment of claims in certain cases, or to realize on certain property received in respect of any such claim as security or otherwise.

Annual Trustee Report to Holders of Debt Securities

        The Trustee is required to submit an annual report to the holders of the debt securities regarding, among other things, the Trustee's eligibility to serve as such, the priority of the Trustee's claims regarding certain advances made by it, and any action taken by the Trustee materially affecting the debt securities.

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Certificates and Opinions to be Furnished to Trustee

        Each Indenture will provide that, in addition to other certificates or opinions that may be specifically required by other provisions of an Indenture, every application by us for action by the Trustee shall be accompanied by a certificate of certain of our officers and an opinion of counsel (who may be our counsel) stating that, in the opinion of the signers, all conditions precedent to such action have been complied with by us.


TAX CONSIDERATIONS

        This section is a summary of material tax considerations that may be relevant to an investment in our securities and, unless otherwise noted in the following discussion, expresses the opinion of Andrews Kurth LLP, our tax counsel, insofar as it relates to matters of United States federal income tax law and legal conclusions with respect to those matters. This section is based upon current provisions of the Internal Revenue Code, existing and proposed regulations thereunder and current administrative rulings and court decisions, all of which are subject to change. Later changes in these authorities may cause the tax consequences to vary substantially from the consequences described below. Unless the context otherwise requires, references in this section to "us" are references to TC PipeLines, LP and our subsidiary operating companies.

        No attempt has been made in the following discussion to comment on all federal income tax matters affecting us or the unitholders. Moreover, the discussion focuses on unitholders who are individual citizens or residents of the United States and has only limited application to corporations, partnerships, estates, trusts, non-resident aliens or other unitholders subject to specialized tax treatment, such as tax-exempt institutions, foreign persons, individual retirement accounts, real estate investment trusts or mutual funds. Accordingly, we recommend that you consult, and depend on your own tax advisor in analyzing the federal, state, local and foreign tax consequences to you of an investment in our securities.

        All statements as to matters of law and legal conclusions, but not as to factual matters, contained in this section, unless otherwise noted, are the opinion of counsel and are based on the accuracy of the representations we make.

        No ruling has been or will be requested from the IRS regarding any matter affecting us or prospective unitholders. An opinion of counsel represents only that counsel's best legal judgment and does not bind the IRS or the courts. Accordingly, the opinions and statements made here may not be sustained by a court if contested by the IRS. Any contest of this sort with the IRS may materially and adversely impact the market for the common units and the prices at which the common units trade. In addition, the costs of any contest with the IRS will be borne directly or indirectly by the unitholders and the general partner. Furthermore, the tax treatment of us, or an investment in us, may be significantly modified by future legislative or administrative changes or court decisions. Any modifications may or may not be retroactively applied.

        For the reasons described below, counsel has not rendered an opinion with respect to the following specific federal income tax issues:

Partnership Status

        A partnership is not a taxable entity and incurs no federal income tax liability. Instead, each partner of a partnership is required to take into account his allocable share of items of income, gain, loss and deduction

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of the partnership in computing his federal income tax liability, regardless of whether cash distributions are made. Distributions of cash by a partnership to a partner are generally not taxable unless the amount of cash distributed to a partner is in excess of the partner's adjusted tax basis in his partnership interest.

        No ruling has been or will be sought from the IRS with respect to our classification as a partnership for federal income tax purposes, whether our operations generate "qualifying income" under Section 7704 of the Internal Revenue Code or any other matter affecting us or prospective unitholders. Instead we have relied on the opinion of counsel that, based upon the Internal Revenue Code, Treasury Regulations, published revenue rulings and court decisions and representations described below, each of TC PipeLines and the intermediate partnerships will each be classified as a partnership for federal income tax purposes.

        In rendering its opinion that we have been and will continue to be treated as partnerships for federal income tax purposes, Andrews Kurth LLP has relied on the factual representations made by us and the general partner, including:

        Section 7704 of the Internal Revenue Code provides that publicly-traded partnerships will, as a general rule, be taxed as corporations. However, an exception, referred to as the "qualifying income exception," exists with respect to publicly-traded partnerships of which 90% or more of the gross income for every taxable year consists of "qualifying income." Qualifying income includes income and gains derived from the transportation and marketing of natural gas. Other types of qualifying income include interest from other than a financial business, dividends, gains from the sale of real property, and gains from the sale or other disposition of capital assets held for the production of income that otherwise constitutes qualifying income. We estimate that less than 3% of our current income is not qualifying income; however, this estimate could change from time to time. Based upon and subject to this estimate, the factual representations made by us and the general partner and a review of the applicable legal authorities, counsel is of the opinion that at least 90% of our gross income constitutes qualifying income.

        If we fail to meet the qualifying income exception, other than a failure which is determined by the IRS to be inadvertent and which is cured within a reasonable time after discovery, we will be treated as if we transferred all of our assets, subject to liabilities, to a newly formed corporation, on the first day of the year in which we fail to meet the qualifying income exception, in return for stock in that corporation, and then distributed that stock to the partners in liquidation of their interests in us. This contribution and liquidation should be tax-free to unitholders and TC PipeLines, so long as we, at that time, do not have liabilities in excess of the tax basis of our assets. Thereafter, we would be treated as a corporation for federal income tax purposes.

        If any of TC PipeLines or the intermediate partnerships were treated as an association taxable as a corporation in any taxable year, either as a result of a failure to meet the qualifying income exception or otherwise, its items of income, gain, loss and deduction would be reflected only on its tax return rather than being passed through to the unitholders, and its net income would be taxed to TC PipeLines or the intermediate partnerships at corporate rates. In addition, any distributions we made to a unitholder would be treated as either taxable dividend income, to the extent of our current or accumulated earnings and profits,

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or, in the absence of earnings and profits, a nontaxable return of capital, to the extent of the unitholder's tax basis in his common units, or taxable capital gain, after the unitholder's tax basis in the common units is reduced to zero. Accordingly, treatment of either TC PipeLines or the intermediate partnerships as an association taxable as a corporation would result in a material reduction in a unitholder's cash flow and after-tax return and thus would likely result in a substantial reduction of the value of the common units.

        The discussion below is based on the assumption that we will be classified as a partnership for federal income tax purposes.

Limited Partner Status

        Unitholders who have become limited partners of TC PipeLines will be treated as partners of TC PipeLines for federal income tax purposes. Assignees who have executed and delivered transfer applications, and are awaiting admission as limited partners, and unitholders whose common units are held in street name or by a nominee and who have the right to direct the nominee in the exercise of all substantive rights attendant to the ownership of their common units will also be treated as partners of TC PipeLines for federal income tax purposes. Because there is no direct authority addressing assignees of common units who are entitled to execute and deliver transfer applications and thereby become entitled to direct the exercise of attendant rights, but who fail to execute and deliver transfer applications, counsel's opinion does not extend to these persons. Furthermore, a purchaser or other transferee of common units who does not execute and deliver a transfer application may not receive certain federal income tax information or reports furnished to record holders of common units unless the common units are held in a nominee or street name account and the nominee or broker has executed and delivered a transfer application for those common units.

        A beneficial owner of common units whose common units have been transferred to a short seller to complete a short sale would appear to lose his status as a partner with respect to such common units for federal income tax purposes. Please read "— Tax Consequences of Unit Ownership — Treatment of Short Sales."

        Income, gain, deductions or losses would not appear to be reportable by a unitholder who is not a partner for federal income tax purposes, and any cash distributions received by a unitholder who is not a partner for federal income tax purposes would therefore be fully taxable as ordinary income. These holders are urged to consult their own tax advisors with respect to their status as partners of TC PipeLines for federal income tax purposes.

Tax Consequences of Unit Ownership

        Flow-through of Taxable Income.    We will not pay any federal income tax. Instead, each unitholder will be required to report on his income tax return his allocable share of our income, gains, losses and deductions without regard to whether corresponding cash distributions are received by that unitholder. Consequently, a unitholder may be allocated a share of our income even if he has not received a cash distribution. Each unitholder must include in income his allocable share of our income, gain, loss and deduction for our taxable year ending with or within his taxable year. Our taxable year ends on December 31.

        Treatment of Distributions.    Our distributions to a unitholder generally will not be taxable to the unitholder for federal income tax purposes to the extent of his tax basis in his common units immediately before the distribution. Our cash distributions in excess of a unitholder's tax basis generally will be considered to be gain from the sale or exchange of the common units, taxable in accordance with the rules described under "— Disposition of Common Units" below. Any reduction in a unitholder's share of our liabilities for which no partner, including the general partner, bears the economic risk of loss, known as "nonrecourse liabilities," will be treated as a distribution of cash to that unitholder. To the extent that our distributions cause a unitholder's "at risk" amount to be less than zero at the end of any taxable year, he must recapture any losses deducted in previous years that are equal to the amount of that shortfall.

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        A decrease in a unitholder's percentage interest in us because of our issuance of additional common units will decrease his share of nonrecourse liabilities, and thus will result in a corresponding deemed distribution of cash. A non-pro rata distribution of money or property may result in ordinary income to a unitholder, regardless of his tax basis in his common units, if that distribution reduces the unitholder's share of our "unrealized receivables," including depreciation recapture, and/or substantially appreciated "inventory items," both as defined in Section 751 of the Internal Revenue Code, and collectively, "Section 751 Assets." To that extent, the unitholder will be treated as having been distributed his proportionate share of the Section 751 Assets and having exchanged those assets with us in return for the non-pro rata portion of the actual distribution made to him. This latter deemed exchange will generally result in the unitholder's realization of ordinary income under Section 751(b) of the Internal Revenue Code. That income will equal the excess of the non-pro rata portion of the distribution over the unitholder's tax basis for the share of the Section 751 Assets deemed relinquished in the exchange.

        Basis of Common Units. A unitholder will have an initial tax basis for his common units equal to the amount he paid for the common units plus his share of our nonrecourse liabilities. That basis will be increased by his share of our income and by any increases in his share of our nonrecourse liabilities. That basis will be decreased, but not below zero, by distributions from us, by his share of our losses, by any decrease in his share of our nonrecourse liabilities and by his share of our expenditures that are not deductible in computing our taxable income and are not required to be capitalized. A limited partner will have no share of our debt which is recourse to the general partner, but will have a share, generally based on his share of profits, of our nonrecourse liabilities.

        Limitations on Deductibility of Our Losses.    The ability of a unitholder to deduct his share of our losses is limited first by his tax basis and the amount he has at risk and, second, the application of the passive loss rules.

        The deduction by a unitholder of his share of our losses will first be limited to his tax basis in his common units and, in the case of an individual unitholder or a corporate unitholder who is subject to the "at risk" rules, to the amount for which the unitholder is considered to be "at risk" with respect to our activities, if that is less than the unitholder's tax basis. A unitholder must recapture losses deducted in previous years to the extent that our distributions cause the unitholder's at risk amount to be less than zero at the end of any taxable year. Losses disallowed to a unitholder or recaptured as a result of these limitations will carry forward and will be allowable to the extent that the unitholder's tax basis or at risk amount, whichever is the limiting factor, subsequently increases. Upon the taxable disposition of a common unit, any gain recognized by a unitholder can be offset by losses that were previously suspended by the at risk limitation but may not be offset by losses suspended by the basis limitation. Any excess loss above that gain previously suspended by the at risk or basis limitations is no longer utilizable.

        In general, a unitholder will be at risk to the extent of his tax basis in his common units, excluding any portion of that basis attributable to his share of our nonrecourse liabilities, reduced by any amount of money the unitholder borrows to acquire or hold his common units if the lender of such borrowed funds owns an interest in us, is related to the unitholder or can look only to common units for repayment. A unitholder's at risk amount will increase or decrease as the tax basis of the unitholder's common units increases or decreases, other than tax basis increases or decreases attributable to increases or decreases in his share of our nonrecourse liabilities.

        The passive loss limitations generally provide that individuals, estates, trusts and certain closely-held corporations and personal service corporations can deduct losses from passive activities, generally, activities in which the taxpayer does not materially participate, only to the extent of the taxpayer's income from those passive activities. The passive loss limitations are applied separately with respect to each publicly-traded partnership. Consequently, any passive losses we generate will only be available to offset future income we generate and will not be available to offset income from other passive activities or investments, including other publicly-traded partnerships, or salary or active business income. Passive losses which are not deductible because they exceed a unitholder's share of our income may be deducted in full when he disposes of his entire investment in us in a fully taxable transaction to an unrelated party. The passive activity loss

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rules are applied after other applicable limitations on deductions, including the at risk rules and the basis limitation.

        A unitholder's share of our net income may be offset by any suspended passive losses we generate, but it may not be offset by any other current or carryover losses from other passive activities, including those attributable to other publicly-traded partnerships.

        Limitations on Interest Deductions.    The deductibility of a non-corporate taxpayer's "investment interest expense" is generally limited to the amount of that taxpayer's "net investment income." Investment interest expense includes:

        The computation of a unitholder's investment interest expense will take into account interest on any margin account borrowing or other loan incurred to purchase or carry a common unit. Net investment income includes gross income from property held for investment and amounts treated as portfolio income pursuant to the passive loss rules less deductible expenses, other than interest, directly connected with the production of investment income, but generally does not include gains attributable to the disposition of property held for investment. The IRS has indicated that net passive income earned by a publicly-traded partnership will be treated as investment income to unitholders. In addition, a unitholder's share of our portfolio income will be treated as investment income.

        Allocation of Income, Gain, Loss and Deduction.    In general, if we have a net profit, our items of income, gain, loss and deduction are allocated among the general partner and the unitholders in accordance with their respective percentage interests in us. At any time that incentive distributions are made to the general partner, gross income is allocated to the general partner to the extent of these distributions. If we have a net loss for the entire year, our items of income, gain, loss and deduction are generally allocated first, to the general partner and the unitholders in accordance with their respective percentage interests to the extent of their positive capital accounts, as maintained under the partnership agreement, and second, to the general partner.

        Specified items of our income, deduction, gain and loss are allocated to account for the difference between the tax basis and fair market value of property contributed or deemed contributed to us by the general partner and its affiliates, and to account for the difference between the fair market value of our assets and their carrying value on our books at the time of any offering made pursuant to this prospectus, referred to in this discussion as "contributed property." The effect of these allocations to a unitholder purchasing common units pursuant to this prospectus will be essentially the same as if the tax basis of our assets were equal to their fair market value at the time of purchase. In addition, items of recapture income are allocated to the extent possible to the partner allocated the deduction giving rise to the treatment of that gain as recapture income in order to minimize the recognition of ordinary income by some unitholders. Finally, although we do not expect that our operations will result in the creation of negative capital accounts to unitholders, if negative capital accounts nevertheless result, items of our income and gain will be allocated in an amount and manner sufficient to eliminate the negative balance as quickly as possible.

        An allocation of items of our income, gain, loss or deduction, other than an allocation required by the Internal Revenue Code to eliminate the difference between a partner's "book" capital account, credited with the fair market value of contributed property, and "tax" capital account, credited with the tax basis of contributed property, will generally be given effect for federal income tax purposes in determining a partner's distributive share of an item of income, gain, loss or deduction only if the allocation has substantial economic effect. In any other case, a partner's distributive share of an item will be determined on the basis of the partner's interest in us, which will be determined by taking into account all the facts and circumstances, including the partners' relative contributions to us, the interests of the partners in economic

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profits and losses, the interest of the partners in cash flow and other nonliquidating distributions and rights of the partners to distributions of capital upon liquidation.

        Counsel is of the opinion that, with the exception of the issues described in "— Tax Consequences of Unit Ownership — Section 754 Election" and "— Disposition of Common Units — Allocations Between Transferors and Transferees," allocations under our partnership agreement will be given effect for federal income tax purposes in determining a partner's distributive share of an item of income, gain, loss or deduction.

        Entity-Level Collections.    If we are required or elect under applicable law to pay any federal, state or local income tax on behalf of any unitholder or the general partner or any former unitholder, we are authorized to pay those taxes from our funds. That payment, if made, will be treated as a distribution of cash to the partner on whose behalf the payment was made. If the payment is made on behalf of a person whose identity cannot be determined, we are authorized to treat the payment as a distribution to current unitholders. We are authorized to amend our partnership agreement in the manner necessary to maintain uniformity of intrinsic tax characteristics of common units and to adjust subsequent distributions, so that after giving effect to these distributions, the priority and characterization of distributions otherwise applicable under our partnership agreement is maintained as nearly as is practicable. Payments by us as described above could give rise to an overpayment of tax on behalf of an individual partner in which event the partner would be required to file a claim in order to obtain a credit or refund.

        Treatment of Short Sales.    A unitholder whose common units are loaned to a "short seller" to cover a short sale of common units may be considered as having disposed of ownership of those common units. If so, he would no longer be a partner with respect to those common units during the period of the loan and may recognize gain or loss from the disposition. As a result, during this period:

        Counsel has not rendered an opinion regarding the treatment of a unitholder whose common units are loaned to a short seller to cover a short sale of common units; therefore, unitholders desiring to assure their status as partners and avoid the risk of gain recognition should modify any applicable brokerage account agreements to prohibit their brokers from borrowing their common units. The IRS has announced that it is actively studying issues relating to the tax treatment of short sales of partnership interests. Please also read "— Disposition of Common Units — Recognition of Gain or Loss."

        Tax Rates.    In general, the highest effective United States federal income tax rate for individuals currently is 35% and the maximum United States federal income rate for net capital gains of an individual is 15% if the asset disposed of was held for more than 12 months at the time of disposition.

        Alternative Minimum Tax.    Each unitholder will be required to take into account his distributive share of any of our items of income, gain, deduction or loss for purposes of the alternative minimum tax. In general, the minimum tax rate for noncorporate taxpayers is 26% on the first $175,000 of alternative minimum taxable income in excess of the exemption amount and 28% on any additional alternative minimum taxable income. Prospective unitholders are urged to consult with their tax advisors as to the impact of an investment in common units on their liability for the alternative minimum tax.

        Section 754 Election.    We have made the election permitted by Section 754 of the Internal Revenue Code. The election is irrevocable without the consent of the IRS. The election generally permits us to adjust a common unit purchaser's tax basis in our assets ("inside basis") under Section 743(b) of the Internal Revenue Code to reflect his purchase price. This election does not apply to a person who purchases units directly from us. The Section 743(b) adjustment belongs to the purchaser and not to other partners. For purposes of this discussion, a partner's inside basis in our assets will be considered to have two components:

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(1) his share of our tax basis in our assets ("common basis") and (2) his Section 743(b) adjustment to that basis.

        Treasury Regulations under Section 743 of the Internal Revenue Code require a partnership that adopts the remedial allocation method (which we have done) to depreciate a portion of the Section 743(b) adjustment attributable to recovery property over the remaining cost recovery period for the Section 704(c) built-in gain. Treasury Regulations under Section 197 similarly require a portion of the Section 743(b) adjustment attributable to amortizable Section 197 intangibles to be amortized over the remaining amortization period for the Section 704(c) built-in gain in such intangibles. Under Treasury Regulation Section 1.167(c)-1(a)(6), a Section 743(b) adjustment attributable to property subject to depreciation under Section 167 of the Internal Revenue Code rather than cost recovery deductions under Section 168 of the Internal Revenue Code is generally required to be depreciated using either the straight-line method or the 150% declining balance method. Under our partnership agreement, we have adopted a convention to preserve the uniformity of common units even if that convention is not consistent with specified Treasury Regulations. Please read "— Uniformity of Common Units."

        Although counsel is unable to opine as to the validity of this method, we depreciate the portion of a Section 743(b) adjustment attributable to unrealized appreciation in the value of contributed property, to the extent of any unamortized Section 704(c) built-in gain, using a rate of depreciation or amortization derived from the depreciation or amortization method and useful life applied to the common basis of the property, or treat that portion as non-amortizable to the extent attributable to property the common basis of which is not amortizable. This method is consistent with the regulations under Section 743 but is arguably inconsistent with Treasury Regulation Section 1.167(c)-1(a)(6). To the extent this Section 743(b) adjustment is attributable to appreciation in value in excess of the unamortized Section 704(c) built-in gain, we will apply the rules described in the Treasury Regulations and legislative history. If we determine that this position cannot reasonably be taken, we may adopt a depreciation or amortization convention under which all purchasers acquiring common units in the same month would receive depreciation or amortization, whether attributable to common basis or Section 743(b) adjustment, based upon the same applicable rate as if they had purchased a direct interest in our assets. This kind of aggregate approach may result in lower annual depreciation or amortization deductions than would otherwise be allowable to specified unitholders. Please read "— Uniformity of Common Units."

        The allocation of the Section 743(b) adjustment must be made in accordance with the Internal Revenue Code. The IRS may seek to reallocate some or all of any Section 743(b) adjustment to goodwill not so allocated by us. Goodwill, as an intangible asset, is generally amortizable over a longer period of time or under a less accelerated method than our tangible assets.

        A Section 754 election is advantageous if the transferee's tax basis in his common units is higher than the common units' share of the aggregate tax basis of our assets immediately prior to the transfer. In that case, as a result of the election, the transferee would have a higher tax basis in his share of our assets for purposes of calculating, among other items, his depreciation and depletion deductions and his share of any gain or loss on a sale of our assets. Conversely, a Section 754 election is disadvantageous if the transferee's tax basis in his common units is lower than such common units' share of the aggregate tax basis of our assets immediately prior to the transfer. Thus, the fair market value of the common units may be affected either favorably or adversely by the election.

        The calculations involved in the Section 754 election are complex and we will make them on the basis of assumptions as to the value of our assets and other matters. The determinations we make may be successfully challenged by the IRS and the deductions resulting from them may be reduced or disallowed altogether. Should the IRS require a different basis adjustment to be made, and should, in our opinion, the expense of compliance exceed the benefit of the election, we may seek permission from the IRS to revoke our Section 754 election. If permission is granted, a subsequent purchaser of common units may be allocated more income than he would have been allocated had the election not been revoked.

Tax Treatment of Operations

        Accounting Method and Taxable Year.    We currently use the year ending December 31 as our taxable year and we have adopted the accrual method of accounting for federal income tax purposes. Each

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unitholder will be required to include in income his allocable share of our income, gain, loss and deduction for our taxable year ending within or with his taxable year. In addition, a unitholder who has a taxable year ending on a date other than December 31 and who disposes of all of his units following the close of our taxable year but before the close of his taxable year must include his allocable share of our income, gain, loss and deduction in income for his taxable year, with the result that he will be required to include in income for his taxable year his share of more than one year of our income, gain, loss and deduction. Please read "— Disposition of Common Units — Allocations Between Transferors and Transferees."

        Tax Basis, Depreciation and Amortization.    The adjusted tax basis of our assets will be used for purposes of computing depreciation and cost recovery deductions and, ultimately adjusted gain or loss on the disposition of these assets. The federal income tax burden associated with the difference between the fair market value of our assets and their tax basis immediately prior to any offering will be borne by the general partner and other unitholders as of that time. Please read "— Tax Treatment of Unitholders — Allocation of Income, Gain, Loss and Deduction."

        To the extent allowable, we may elect to use the depreciation and cost recovery methods that will result in the largest deductions being taken in the early years after assets are placed in service. We will not be entitled to any amortization deductions with respect to any goodwill conveyed to us on formation. Property we subsequently acquire or construct may be depreciated using accelerated methods permitted by the Internal Revenue Code.

        If we dispose of depreciable property by sale, foreclosure, or otherwise, all or a portion of any gain, determined by reference to the amount of depreciation previously deducted and the nature of the property, may be subject to the recapture rules and taxed as ordinary income rather than capital gain. Similarly, a partner who has taken cost recovery or depreciation deductions with respect to property we own may be required to recapture those deductions as ordinary income upon a sale of his interest in us. Please read "— Tax Consequences of Unit Ownership — Allocation of Income, Gain, Loss and Deduction" and "— Disposition of Common Units — Recognition of Gain or Loss."

        The costs incurred in promoting the issuance of common units (i.e. syndication expenses) must be capitalized and cannot be deducted currently, ratably or upon our termination. Uncertainties exist regarding the classification of costs as organization expenses, which may be amortized, and as syndication expenses, which may not be amortized. The underwriting discounts and commissions we incur are treated as syndication costs.

        Valuation and Tax Basis of Our Properties.    The federal income tax consequences of the ownership and disposition of common units will depend in part on our estimates as to the relative fair market values, and determinations of the initial tax bases, of our assets. Although we may from time to time consult with professional appraisers with respect to valuation matters, we will make many of the relative fair market value estimates ourselves. These estimates and determinations of basis are subject to challenge and will not be binding on the IRS or the courts. If the estimates of fair market value or determinations of basis are later found to be incorrect, the character and amount of items of income, gain, loss or deductions previously reported by unitholders might change, and unitholders might be required to adjust their tax liability for prior years.

Disposition of Common Units

        Recognition of Gain or Loss.    A unitholder will recognize gain or loss on a sale of common units equal to the difference between the amount realized and the unitholder's tax basis for the common units sold. A unitholder's amount realized will be measured by the sum of the cash or the fair market value of other property received plus his share of our nonrecourse liabilities. Because the amount realized includes a unitholder's share of our nonrecourse liabilities, the gain recognized on the sale of common units could result in a tax liability in excess of any cash received from the sale.

        Prior distributions from us in excess of cumulative net taxable income for a common unit that decreased a unitholder's tax basis in that common unit will, in effect, become taxable income if the common unit is sold at a price greater than the unitholder's tax basis in that common unit, even if the price is less than his original cost.

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        Except as noted below, gain or loss recognized by a unitholder, other than a "dealer" in common units, on the sale or exchange of a common unit will generally be taxable as capital gain or loss. Capital gain recognized on the sale of common units held for more than 12 months will generally be taxed at a maximum rate of 15%. A portion of this gain or loss, which could be substantial, however, will be separately computed and taxed as ordinary income or loss under Section 751 of the Internal Revenue Code to the extent attributable to assets giving rise to depreciation recapture or other "unrealized receivables" or to "inventory items" we own. The term "unrealized receivables" includes potential recapture items, including depreciation recapture. Ordinary income attributable to unrealized receivables, inventory items and depreciation recapture may exceed net taxable gain realized upon the sale of the common unit and may be recognized even if there is a net taxable loss realized on the sale of the common unit. Thus, a unitholder may recognize both ordinary income and a capital loss upon a disposition of common units. Net capital loss may offset no more than $3,000 of ordinary income in the case of individuals and may only be used to offset capital gain in the case of corporations.

        The IRS has ruled that a partner who acquires interests in a partnership in separate transactions must combine those interests and maintain a single adjusted tax basis for all those interests. Upon a sale or other disposition of less than all of those interests, a portion of that tax basis must be allocated to the interests sold using an "equitable apportionment" method. On the other hand, a selling unitholder who can identify common units transferred with an ascertainable holding period may elect to use the actual holding period of the units transferred. A unitholder electing to use the actual holding period of common units transferred must consistently use that identification method for all subsequent sales or exchanges of common units.

        Specific provisions of the Internal Revenue Code affect the taxation of some financial products and securities, including partnership interests by treating a taxpayer as having sold an "appreciated" partnership interest, one in which gain would be recognized if it were sold, assigned or otherwise terminated at its fair market value, if the taxpayer or a related person enters into a short sale, an offsetting notional principal contract or a futures or forward contract with respect to the partnership interest or substantially identical property.

        Moreover, if a taxpayer has previously entered into a short sale, an offsetting notional principal contract or a futures or forward contract with respect to a partnership interest, the taxpayer will be treated as having sold that position if the taxpayer or a related person then acquires the partnership interest or substantially similar property. The Secretary of the Treasury is also authorized to issue regulations that treat a taxpayer that enters into transactions or positions that have substantially the same effect as the preceding transactions as having constructively sold the financial position.

        Allocations Between Transferors and Transferees.    In general, our taxable income and losses are determined annually, are prorated on a monthly basis and are subsequently apportioned among the unitholders in proportion to the number of common units owned by each of them as of the opening of the NASDAQ National Market on the first business day of the month (the "Allocation Date"). However, gain or loss realized on a sale or other disposition of our assets other than in the ordinary course of business is allocated among the unitholders on the Allocation Date in the month in which that gain or loss is recognized. As a result, a unitholder transferring common units in the open market may be allocated income, gain, loss and deduction accrued after the date of transfer.

        The use of this method may not be permitted under existing Treasury Regulations. Accordingly, counsel is unable to opine on the validity of this method of allocating income and deductions between the transferors and the transferees of common units. If this method is not allowed under the Treasury Regulations, or only applies to transfers of less than all of the unitholder's interest, our taxable income or losses might be reallocated among the unitholders. We are authorized to revise our method of allocation between transferors and transferees, as well as among partners whose interests otherwise vary during a taxable period, to conform to a method permitted under future Treasury Regulations.

        A unitholder who owns common units at any time during a quarter and who disposes of these common units prior to the record date set for a cash distribution with respect to that quarter will be allocated items of our income, gain, loss and deductions attributable to that quarter but will not be entitled to receive that cash distribution.

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        Notification Requirements.    A unitholder who sells or exchanges common units is required to notify us in writing of that sale or exchange within 30 days after the sale or exchange. We are required to notify the IRS of that transaction and to furnish specified information to the transferor and transferee. However, these reporting requirements do not apply with respect to a sale by an individual who is a citizen of the United States and who effects the sale or exchange through a broker. Additionally, a transferee of a common unit will be required to furnish a statement to the IRS, filed with its income tax return for the taxable year in which the sale or exchange occurred, that sets forth the amount of the consideration paid for the common unit. Failure to satisfy these reporting obligations may lead to the imposition of substantial penalties.

        Constructive Termination.    We will be considered to have been terminated if there is a sale or exchange of 50% or more of the total interests in our capital and profits within a 12-month period. A termination of TC PipeLines will cause a termination of the intermediate partnerships. Our termination would result in the closing of our taxable year for all unitholders. In the case of a unitholder reporting on a taxable year other than a fiscal year ending December 31, the closing of the taxable year may result in more than 12 months of our taxable income or loss being includable in his taxable income for the year of termination. We would be required to make new tax elections after a termination, including a new election under Section 754 of the Internal Revenue Code, and a termination could result in a deferral of our deductions for depreciation. A termination could also result in penalties if we were unable to determine that the termination had occurred. Moreover, a termination might either accelerate the application of, or subject us to, any tax legislation enacted before to the termination.

Uniformity of Common Units

        Because we cannot match transferors and transferees of common units, uniformity of the economic and tax characteristics of the common units to a purchaser of these common units must be maintained. In the absence of uniformity, compliance with a number of federal income tax requirements, both statutory and regulatory, could be substantially diminished. A lack of uniformity can result from a literal application of Treasury Regulation Section 1.167(c)-1(a)(6). Any non-uniformity could have a negative impact on the value of the common units. Please read "— Tax Consequences of Unit Ownership — Section 754 Election."

        Consistent with the regulations under Section 743, we depreciate the portion of a Section 743(b) adjustment attributable to unrealized appreciation in the value of contributed property, to the extent of any unamortized Section 704(c) built-in gain, using a rate of depreciation or amortization derived from the depreciation or amortization method and useful life applied to the common basis of that property, or treat that portion as nonamortizable, to the extent attributable to property the common basis of which is not amortizable. This method is consistent with the regulations under Section 743, but is arguably inconsistent with Treasury Regulation Section 1.167(c)-1(a)(6). To the extent that the Section 743(b) adjustment is attributable to appreciation in value in excess of the unamortized Section 704(c) built-in gain, we apply the rules described in the Treasury Regulations and legislative history. If we determine that this position cannot reasonably be taken, we may adopt a depreciation and amortization convention under which all purchasers acquiring common units in the same month would receive depreciation and amortization deductions, whether attributable to common basis or Section 743(b) adjustment, based upon the same applicable rate as if they had purchased a direct interest in our property.

        If this kind of aggregate approach is adopted, it may result in lower annual depreciation and amortization deductions than would otherwise be allowable to some unitholders and risk the loss of depreciation and amortization deductions not taken in the year that these deductions are otherwise allowable. This convention will not be adopted if we determine that the loss of depreciation and amortization deductions will have a material adverse effect on the unitholders. If we choose not to utilize this aggregate method, we may use any other reasonable depreciation and amortization convention to preserve the uniformity of the intrinsic tax characteristics of any common units that would not have a material adverse effect on the unitholders. The IRS may challenge any method of depreciating the Section 743(b) adjustment described in this paragraph. If this type of challenge were sustained, the uniformity of common units might be affected, and the gain from the sale of common units might be increased without the benefit of additional deductions. Please read "— Disposition of Common Units — Recognition of Gain or Loss."

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Tax-Exempt Organizations and Other Investors

        Ownership of common units by employee benefit plans, other tax-exempt organizations, nonresident aliens, foreign corporations, other foreign persons and regulated investment companies raises issues unique to those investors and, as described below, may have substantially adverse tax consequences. Employee benefit plans and most other organizations exempt from federal income tax, including individual retirement accounts and other retirement plans, are subject to federal income tax on unrelated business taxable income. Virtually all of our taxable income allocated to a unitholder which is a tax-exempt organization will be unrelated business taxable income and will be taxable to that unitholder.

        A regulated investment company or "mutual fund" is required to derive 90% or more of its gross income from interest, dividends, gains from the sale of stocks or securities or foreign currency or specified related sources. It is not anticipated that any significant amount of our gross income will include that type of income. The American Jobs Creation Act of 2004, signed into law on October 22, 2004, also includes net income derived from the ownership of an interest in a "qualified publicly traded partnership" as qualified income to a regulated investment company. We expect that we will meet the definition of a qualified publicly traded partnership. However, this legislation is only effective for taxable years beginning after October 22, 2004.

        Non-resident aliens and foreign corporations, trusts or estates which hold common units will be considered to be engaged in business in the United States on account of ownership of common units. As a consequence they will be required to file federal tax returns in respect of their share of our income, gain, loss or deduction and pay federal income tax at regular rates on any net income or gain. Generally, a partnership is required to pay a withholding tax on the portion of the partnership's income which is effectively connected with the conduct of a United States trade or business and which is allocable to the foreign partners, regardless of whether any actual distributions have been made to such partners. However, under rules applicable to publicly-traded partnerships, we will withhold at applicable rates on actual cash distributions made quarterly to foreign unitholders. Each foreign unitholder must obtain a taxpayer identification number from the IRS and submit that number to our transfer agent on a Form W-8 BEN in order to obtain credit for the taxes withheld. A change in applicable law may require us to change these procedures.

        Because a foreign corporation which owns common units will be treated as engaged in a United States trade or business, that corporation may be subject to United States branch profits tax at a rate of 30%, in addition to regular federal income tax, on its allocable share of our income and gain, as adjusted for changes in the foreign corporation's "U.S. net equity," which are effectively connected with the conduct of a United States trade or business. An income tax treaty between the United States and the country in which the foreign corporate unitholder is a "qualified resident" may reduce or eliminate this tax. In addition, such a unitholder is subject to special information reporting requirements under Section 6038C of the Internal Revenue Code.

        Under a ruling of the IRS, a foreign unitholder who sells or otherwise disposes of a common unit will be subject to federal income tax on gain realized on the disposition of that common unit to the extent that this gain is effectively connected with a United States trade or business of the foreign unitholder. Apart from the ruling, a foreign unitholder will not be taxed upon the disposition of a common unit if that foreign unitholder has held no more than 5% in value of the common units during the five-year period ending on the date of the disposition and if the common units are regularly traded on an established securities market at the time of the disposition.

Administrative Matters

        Information Returns and Audit Procedures.    We intend to furnish to each unitholder, within 90 days after the close of each calendar year, specific tax information, including a Schedule K-1, which describes each unitholder's share of our income, gain, loss and deduction for our preceding taxable year. In preparing this information, which will generally not be reviewed by counsel, we will use various accounting and reporting conventions, some of which have been mentioned in the previous discussion, to determine the unitholder's share of income, gain, loss and deduction. Any of these conventions may not yield a result which conforms

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to the requirements of the Internal Revenue Code, Treasury Regulations or administrative interpretations of the IRS. The IRS may successfully contend in court that those accounting and reporting conventions are impermissible. Any challenge by the IRS could negatively affect the value of the common units.

        The IRS may audit our federal income tax information returns. Adjustments resulting from an audit of this kind may require each unitholder to adjust a prior year's tax liability, and possibly may result in an audit of the unitholder's own return. Any audit of a unitholder's return could result in adjustments not related to our returns as well as those related to our returns.

        Partnerships generally are treated as separate entities for purposes of federal tax audits, judicial review of administrative adjustments by the IRS and tax settlement proceedings. The tax treatment of partnership items of income, gain, loss and deduction are determined in a partnership proceeding rather than in separate proceedings with the partners. The Internal Revenue Code provides for one partner to be designated as the "tax matters partner" for these purposes. Our partnership agreement appoints the general partner as our tax matters partner.

        The tax matters partner will make some elections on our behalf and on behalf of the unitholders and can extend the statute of limitations for assessment of tax deficiencies against unitholders with respect to items in our returns. The tax matters partner may bind a unitholder with less than a 1% profits interest in us to a settlement with the IRS unless that unitholder elects, by filing a statement with the IRS, not to give that authority to the tax matters partner. The tax matters partner may seek judicial review, by which all the unitholders are bound, of a final partnership administrative adjustment and, if the tax matters partner fails to seek judicial review, judicial review may be sought by any unitholder having at least a 1% interest in our profits and by the unitholders having in the aggregate at least a 5% profits interest. However, only one action for judicial review will go forward, and each unitholder with an interest in the outcome may participate.

        A unitholder must file a statement with the IRS identifying the treatment of any item on his federal income tax return that is not consistent with the treatment of the item on our return. Intentional or negligent disregard of the consistency requirement may subject a unitholder to substantial penalties.

        Nominee Reporting.    Persons who hold an interest in us as a nominee for another person are required to furnish to us:

        Brokers and financial institutions are required to furnish additional information, including whether they are United States persons and specific information on common units they acquire, hold or transfer for their own account. A penalty of $50 per failure, up to a maximum of $100,000 per calendar year, is imposed by the Internal Revenue Code for failure to report such information to us. The nominee is required to supply the beneficial owner of the common units with the information furnished to us.

        Registration as a Tax Shelter.    Prior to the enactment of new legislation, the Internal Revenue Code required that "tax shelters" be registered with the Secretary of the Treasury. The American Jobs Creation Act of 2004 eliminated this tax shelter registration requirement. Although we may not have been subject to

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the registration requirement on the basis that we would not constitute a tax shelter, we registered as a tax shelter with the Secretary of the Treasury in light of the substantial penalties which might be imposed if registration was required and not undertaken.

        Reportable Transactions.    Treasury regulations require taxpayers to report certain information on IRS Form 8886 if they participate in a "reportable transaction." Unitholders may be required to file this form with the IRS if we participate in a "reportable transaction." A transaction may be a reportable transaction based upon any of several factors. Each unitholder is urged to consult with his own tax advisor concerning the application of any of these factors to his ownership of common units. The American Jobs Creation Act of 2004 contains provisions that impose significant penalties for failure to comply with these disclosure requirements. This new legislation also imposes disclosure and information maintenance obligations on "material advisors" that organize, manage, promote, sell, implement, insure or carry out any "reportable transaction." Each common unitholder is urged to consult his own tax advisor concerning any possible disclosure obligation with respect to his ownership of common units and should be aware that we and our material advisors intend to comply with the information maintenance and disclosure requirements.

        Accuracy-Related Penalties.    An additional tax equal to 20% of the amount of any portion of an underpayment of tax which is attributable to one or more specified causes, including negligence or disregard of rules or regulations, substantial understatements of income tax and substantial valuation misstatements, is imposed by the Internal Revenue Code. No penalty will be imposed, however, with respect to any portion of an underpayment if it is shown that there was a reasonable cause for that portion and that the taxpayer acted in good faith with respect to that portion.

        A substantial understatement of income tax in any taxable year exists if the amount of the understatement exceeds the greater of 10% of the tax required to be shown on the return for the taxable year or $5,000 ($10,000 for most corporations). The amount of any understatement subject to penalty generally is reduced if any portion is attributable to a position adopted on the return:

        More stringent rules apply to "tax shelters," a term that in this context does not appear to include us. If any item of our income, gain, loss or deduction included in the distributive shares of unitholders might result in an "understatement" of income for which no "substantial authority" exists, we must disclose the pertinent facts on our return. In addition, we will make a reasonable effort to furnish sufficient information for unitholders to make adequate disclosure on their returns to avoid liability for this penalty.

        A substantial valuation misstatement exists if the value of any property, or the adjusted basis of any property, claimed on a tax return is 200% or more of the amount determined to be the correct amount of such valuation or adjusted basis. No penalty is imposed unless the portion of the underpayment attributable to a substantial valuation misstatement exceeds $5,000 ($10,000 for most corporations). If the valuation claimed on a return is 400% or more than the correct valuation, the penalty imposed increases to 40%.

State, Local and Other Tax Considerations

        In addition to federal income taxes, a unitholder will be subject to other taxes, including state and local income taxes, unincorporated business taxes, and estate, inheritance or intangible taxes that may be imposed by the various jurisdictions in which he resides or in which we do business or own property. Although an analysis of those various taxes is not presented here, each prospective unitholder should consider their potential impact on his investment in us. A unitholder will be required to file state income tax returns and to pay state income taxes in some or all of the states in which we do business or own property and may be subject to penalties for failure to comply with those requirements. In some states, tax losses may not produce a tax benefit in the year incurred and also may not be available to offset income in subsequent taxable years. Some of the states may require us, or we may elect, to withhold a percentage of income from amounts to be distributed to a unitholder who is not a resident of the state. Withholding, the amount of which may be

37


greater or less than a particular unitholder's income tax liability to the state, generally does not relieve the non-resident unitholder from the obligation to file an income tax return. Amounts withheld may be treated as if distributed to unitholders for purposes of determining the amounts distributed by us. Please read "— Tax Consequences of Unit Ownership — Entity-Level Collections." Based on current law and our estimate of future operations, our general partner anticipates that any amounts required to be withheld will not be material.

        It is the responsibility of each unitholder to investigate the legal and tax consequences under the laws of pertinent states and localities of his investment in us. Accordingly, we recommend that each prospective unitholder consult, and depend upon, his own tax counsel or other advisor with regard to those matters. Further, it is the responsibility of each unitholder to file all state and local, as well as U.S. federal, tax returns that may be required of him. Counsel has not rendered an opinion on the state or local tax consequences of an investment in us.

Tax Consequences of Ownership of Debt Securities

        A description of the material federal income tax consequences of the ownership and disposition of debt securities will be included in the prospectus supplement relating to the offering of debt securities.


INVESTMENT IN US BY EMPLOYEE BENEFIT PLANS

        An investment in us by an employee benefit plan is subject to additional considerations because the investments of such plans are subject to the fiduciary responsibility and prohibited transaction provisions of the Employee Retirement Income Security Act of 1974, as amended, and restrictions imposed by Section 4975 of the Internal Revenue Code. As used herein, the term "employee benefit plan" includes, but is not limited to, qualified pension, profit-sharing and stock bonus plans, Keogh plans, Simplified Employee Pension Plans, and tax deferred annuities or Individual Retirement Accounts established or maintained by an employer or employee organization. Among other things, consideration should be given to:

        The person with investment discretion with respect to the assets of an employee benefit plan should determine whether an investment in us is authorized by the appropriate governing instrument and is a proper investment for such plan.

        In addition, a fiduciary of an employee benefit plan should consider whether such plan will, by investing in us, be deemed to own an undivided interest in our assets. If so, the general partner also would be a fiduciary of such plan, and we would be subject to the regulatory restrictions of ERISA, including its prohibited transaction rules, as well as the prohibited transaction rules of the Internal Revenue Code.

        Section 406 of ERISA and Section 4975 of the Internal Revenue Code prohibit an employee benefit plan from engaging in transactions involving "plan assets" with parties that are "parties in interest" under ERISA or "disqualified persons" under the Internal Revenue Code with respect to the plan. These provisions also apply to Individual Retirement Accounts which are not considered part of an employee benefit plan. The Department of Labor issued final regulations on November 13, 1986 that provide guidance with respect to whether the assets of an entity in which employee benefit plans acquire equity interests would be deemed "plan assets." Pursuant to these regulations, an entity's assets would not be considered to be "plan assets" if, among other things,

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        Our assets would not be considered "plan assets" under these regulations because it is expected that the investment will satisfy the requirements in (1) above. Plan fiduciaries contemplating a purchase of common units should consult with their own counsel regarding the consequences under ERISA and the Internal Revenue Code in light of the serious penalties imposed on persons who engage in prohibited transactions or other violations.


SELLING UNITHOLDERS

        In addition to covering our offering of securities, this prospectus covers the offering for resale of up to 5,609,306 common units by the Selling Unitholders. The information in the table below is as of the date of this prospectus. TransCan Northern Ltd. and TC PipeLines GP, Inc. are indirect wholly owned subsidiaries of TransCanada. TC PipeLines GP, a wholly owned subsidiary of TransCan Northern, is our general partner.

Name
   Number of
Common Units
Owned
   Number of
Common Units
Available for
Resale
   Number of
Common Units
Available After
Resale(1)
TransCan Northern Ltd.
450 - 1st Street S.W.
Calgary, Alberta T2P 5H1
Canada		   2,800,000   2,800,000   —

TC PipeLines GP, Inc.
450 - 1st Street S.W.
Calgary, Alberta T2P 5H1
Canada
 
2,809,306
 
2,809,306
 
—
(1)
The number of common units shown in this column assumes that the selling unitholder sells all of the common units offered by this prospectus and that, prior to the sale of such common units, the selling unitholder does not acquire additional common units. The selling unitholder may sell none, some or all of the common units offered pursuant to this prospectus or may acquire additional common units.

        The applicable prospectus supplement will set forth, with respect to the Selling Unitholders:

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        All expenses incurred with the registration of the common units owned by the Selling Unitholders, excluding any separate legal fees and expenses of the Selling Unitholders, will be borne by us.


PLAN OF DISTRIBUTION

        We and the Selling Unitholders may sell the securities covered by this prospectus either separately or concurrently.

Sales of Securities by Us

        We may sell the securities being offered hereby:

        We, or agents designated by us, may directly solicit, from time to time, offers to purchase the securities. Any such agent may be deemed to be an underwriter as that term is defined in the Securities Act of 1933, as amended. We will name the agents involved in the offer or sale of the securities and describe any commissions payable by us or to these agents in the prospectus supplement. Unless otherwise indicated in the prospectus supplement, these agents will be acting on a best efforts basis for the period of their appointment. The agents may be entitled under agreements which may be entered into with us to indemnification by us against specific civil liabilities, including liabilities under the Securities Act. The agents may also be our customers or may engage in transactions with or perform services for us in the ordinary course of business.

        If we utilize any underwriters in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement with those underwriters at the time of sale to them. We will set forth the names of these underwriters and the terms of the transaction in the prospectus supplement, which will be used by the underwriters to make resales of the securities in respect of which this prospectus is delivered to the public. The underwriters may be entitled, under the relevant underwriting agreement, to indemnification by us against specific liabilities, including liabilities under the Securities Act. The underwriters may also be our customers or may engage in transactions with or perform services for us in the ordinary course of business.

        If we utilize a dealer in the sale of the securities in respect of which this prospectus is delivered, we will sell those securities to the dealer, as principal. The dealer may then resell those securities to the public at varying prices to be determined by the dealer at the time of resale. Dealers may be entitled to indemnification by us against specific liabilities, including liabilities under the Securities Act. The dealers may also be our customers or may engage in transactions with or perform services for us in the ordinary course of business.

        We may engage Brinson Patrick Securities Corporation and/or one or more other firms to act as our agent (the "Offering Agent") for one or more offerings, from time to time, of our common units. If we reach agreement with the Offering Agent with respect to a specific offering, including the number of common units and any minimum price below which sales may not be made, then the Offering Agent would agree to use its commercially reasonable efforts, consistent with its normal trading and sales practices, to try to sell such common units on the agreed terms. The Offering Agent could make sales in privately negotiated transactions and/or any other method permitted by law, including sales deemed to be an "at the market" offering as defined in Rule 415 promulgated under the Securities Act, including sales made to or through a market maker other than on an exchange. At-the-market offerings may not exceed 10% of the aggregate market value of our outstanding voting securities held by non-affiliates on a date within 60 days prior to the filing of the registration statement of which this prospectus is a part. The Offering Agent will be deemed to be an "underwriter" within the meaning of the Securities Act of 1933, with respect to any sales effected through an "at the market" offering.

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        Common units and debt securities may also be sold directly by us. In this case, no underwriters or agents would be involved. We may use electronic media, including the Internet, to sell offered securities directly.

        To the extent required, this prospectus may be amended or supplemented from time to time to describe a specific plan of distribution. The place and time of delivery for the securities in respect of which this prospectus is delivered are set forth in the accompanying prospectus supplement.

Sales of Common Units by the Selling Unitholders

        Upon registration pursuant to the registration rights agreement, the Selling Unitholders may sell the common units offered by this prospectus from time to time using any one or more of the following methods:


        The Selling Unitholders may also sell common units under Rule 144 under the Securities Act, if available, rather than under this prospectus.

        Broker-dealers engaged by the Selling Unitholders may arrange for other broker-dealers to participate in sales. Broker-dealers may receive commissions or discounts from the Selling Unitholders (or, if any broker-dealer acts as agent for the purchaser of common units, from the purchaser) in amounts to be negotiated. The Selling Unitholders do not expect these commissions and discounts to exceed what is customary in the types of transactions involved.

        The Selling Unitholders and any broker-dealers or agents that are involved in selling the common units may be deemed to be "underwriters" within the meaning of the Securities Act in connection with such sales. In such event, any commissions received by such broker-dealers or agents and any profit on the resale of the common units purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. The Selling Unitholders have informed us that they do not have any agreement or understanding, directly or indirectly, with any person to distribute the common units.

        Under the terms of our partnership agreement, we are obligated to pay all of the costs and expenses of the Selling Unitholders in connection with the registration and any offering of the common units registered by the Selling Unitholders, other than underwriting discounts and commissions.

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LEGAL

        Certain legal and tax matters in connection with the securities will be passed upon by Andrews Kurth LLP, Houston, Texas, as our counsel. Any underwriter will be advised about other issues relating to the offering by their own legal counsel.


EXPERTS

        The consolidated financial statements of TC PipeLines, LP and its subsidiaries as at December 31, 2003 and 2002 and for each of the years in the three-year period ended December 31, 2003, have been incorporated by reference herein, in reliance upon the report of KPMG LLP, independent chartered accountants, and upon the authority of said firm as experts in accounting and auditing.

        The financial statements and schedule of Northern Border Pipeline Company as of December 31, 2003 and 2002 and for each of the years in the three-year period ended December 31, 2003, have been incorporated by reference herein, in reliance upon the report of KPMG LLP, independent registered public accountants, and upon the authority of said firm as experts in accounting and auditing.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 14.    OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION

        The following table sets forth the costs and expenses we will incur in connection with the offering of the securities being registered. All amounts other than the Securities and Exchange Commission registration fee are estimated.

Securities and Exchange Commission registration fee   54,282
Legal fees and expenses   110,000
Accounting fees and expenses   40,000
Printing expenses   40,000
Transfer Agent and Registrar fees and expenses   15,000
Miscellaneous   10,000
   
  Total   269,282
   

ITEM 15.    INDEMNIFICATION OF DIRECTORS AND OFFICERS

        Section 17-108 of the Delaware Revised Uniform Limited Partnership Act empowers a Delaware limited partnership to indemnify and hold harmless any partner or other person from and against all claims and demands whatsoever.

        Section 7.7(a) of the Amended and Restated Agreement of Limited Partnership ("Partnership Agreement") of TC PipeLines, LP provides that to the fullest extent permitted by law, all Indemnitees (as defined below) shall be indemnified and held harmless by the Partnership from and against any and all losses, claims, damages, liabilities (joint or several), expenses (including legal fees and expenses), judgments, fines, penalties, interest, settlements or other amounts arising from any and all claims, demands, actions, suits or proceedings, whether civil, criminal, administrative or investigative, in which any Indemnitee may be involved, or is threatened to be involved, as a party or otherwise, by reason of its status as an Indemnitee; provided, that in each case the Indemnitee acted in good faith and in a manner that such Indemnitee reasonably believed to be in, or (in the case of a Person other than the General Partner) not opposed to, the best interests of the Partnership and, with respect to any criminal proceeding, had no reasonable cause to believe its conduct was unlawful. The Partnership Agreement defines an Indemnitee as: (i) the General Partner, (ii) any Departing Partner, (iii) any Person who is or was an Affiliate of the General Partner or any Departing Partner, (iv) any Person who is or was a member, partner, officer, director, employee, agent or trustee of the Partnership, any intermediate partnership and any majority owned subsidiary of such entity (each, a "Group Member"), the General Partner or any Departing Partner or any Affiliate of any Group Member, the General Partner or any Departing Partner, and (v) any Person who is or was serving at the request of the General Partner or any Departing Partner or any Affiliate of the General Partner or any Departing Partner as an officer, director, employee, member, partner, agent or trustee of another Person; provided, that a Person shall not be an Indemnitee by reason of providing, on a fee-for-services basis, trustee, fiduciary or custodial services.

        Section 7.7(b) of the Partnership Agreement also states that to the fullest extent permitted by law, expenses (including legal fees and expenses) incurred by an Indemnitee who is indemnified pursuant to Section 7.7(a) in defending any claim, demand, action, suit or proceeding shall, from time to time, be advanced by the Partnership prior to the final disposition of such claim, demand, action, suit or proceeding upon receipt by the Partnership of any undertaking by or on behalf of the Indemnitee to repay such amount if it shall be determined that the Indemnitee is not entitled to be indemnified as authorized by Section 7.7(a).

        Section 7.7(g) of the Partnership Agreement states that an Indemnitee shall not be denied indemnification in whole or in part under Section 7.7 because the Indemnitee has an interest in the

II-1


transaction with respect to which the indemnification applies if the transaction was otherwise permitted by the terms of the Partnership Agreement.

        Section 7.8(a) of the Partnership Agreement provides that notwithstanding anything to the contrary set forth in the Partnership Agreement, no Indemnitee shall be liable for monetary damages to the Partnership, the limited partners of the Partnership, the assignees or any other Persons who have acquired securities of the Partnership, for losses sustained or liabilities incurred as a result of any act or omission if such Indemnitee acted in good faith.

        Section 7.8(b) of the Partnership Agreement states that the General Partner, subject to its obligations and duties as General Partner set forth in Section 7.1(a) of the Partnership Agreement, may exercise any of the powers granted to it by the Partnership Agreement and perform any of the duties imposed upon it hereunder either directly or by or through its agents, and the General Partner shall not be responsible for any misconduct or negligence on the part of any such agent appointed by the General Partner in good faith.

        Additionally, Section 7.8(c) provides that to the extent that, at law or in equity, an Indemnitee has duties (including fiduciary duties) and liabilities relating thereto to the Partnership or to the partners, the General Partner and any other Indemnitee acting in connection with the Partnership's business or affairs shall not be liable to the Partnership or to any partner for its good faith reliance on the provisions of the Partnership Agreement. The provisions of the Partnership Agreement, to the extent that they restrict or otherwise modify the duties and liabilities of an Indemnitee otherwise existing at law or in equity, are agreed by the partners to replace such other duties and liabilities of such Indemnitee.

        Any underwriting agreement entered into in connection with the sale of the securities offered pursuant to this registration statement will provide for indemnification of officers and directors of the General Partner.

ITEM 16.    EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

(a)
Exhibits

*1.1   Form of Underwriting Agreement related to Common Units
*1.2   Form of Underwriting Agreement related to Senior Debt
*1.3   Form of Underwriting Agreement related to Subordinated Debt
*1.4   Form of Sales Agreement
**4.1   Form of certificate representing the Common Units of TC PipeLines, LP (filed as Exhibit A to Appendix A to TC PipeLines' Registration Statement on Form S-1 (Registration No. 333-69947) and incorporated by reference herein)
4.2   Form of Senior Indenture
4.3   Form of Subordinated Indenture
**4.4   Amended and Restated Agreement of Limited Partnership of TC PipeLines, LP (incorporated by reference from Exhibit 3.1 to the Registrant's Form 10-K, File No. 000-26091, filed on March 28, 2000)
5.1   Opinion of Andrews Kurth LLP as to the legality of the securities registered hereby
8.1   Opinion of Andrews Kurth LLP as to tax matters
12.1   Computation of ratio of earnings to fixed charges
23.1   Consent of KPMG LLP (TC PipeLines, LP)
23.2   Consent of KPMG LLP (Northern Border Pipeline Company)
23.3   Consents of Andrews Kurth LLP (included in Exhibits 5.1 and 8.1)
24.1   Power of Attorney (included on signature page)
*99.1   Form T-1 Statement of Eligibility and Qualification related to the Senior Indenture and the Subordinated Indenture
*
To be filed by a post-effective amendment or as an exhibit to a Current Report on Form 8-K.

**
Incorporated by reference.

II-2

(b)
Financial Statement Schedules

        No financial statement schedules are included herein. All other schedules for which provision is made in the applicable accounting regulation of the Securities and Exchange Commission are not required under the related instructions, are inapplicable, or the information is included in the consolidated financial statements, and have therefore been omitted.

(c)
Reports, Opinions, and Appraisals

        The following reports, opinions, and appraisals are included herein: None

ITEM 17.    UNDERTAKINGS

        Insofar as indemnification for liabilities arising under the Securities Act of 1933, as amended (the "Securities Act"), may be permitted to directors, officers and/or persons controlling the registrant pursuant to the foregoing provisions, the registrant has been informed that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

        In the event that a claim for indemnification against such liabilities (other than the payment by TC PipeLines, LP of expenses incurred or paid by a director, officer or controlling person of TC PipeLines, LP in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, TC PipeLines, LP will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

        The undersigned registrant hereby undertakes:

        The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the registrant's annual report pursuant to section 13(a) or section 15(d) of the Exchange Act that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

II-3


SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized in the City of Calgary, Province of Alberta, Canada on December 22, 2004.

    TC PIPELINES, LP

 
 
By:
TC PIPELINES GP, INC.,
its General Partner

 
 
By:
/s/  RONALD J. TURNER      
Ronald J. Turner
President and Chief Executive Officer
TC PipeLines GP, Inc.

II-4


POWER OF ATTORNEY

        Each person whose signature appears below appoints Russell K. Girling and Maryse C. St.-Laurent, and each of them, any of whom may act without the joinder of the other, as his true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement and any Registration Statement (including any amendment thereto) for this offering that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act of 1933, as amended, and to file the same, with all exhibits thereto, and all other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done, as fully to all intents and purposes as he might or would do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them of their or his substitute and substitutes, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed below by the following persons in the capacities and on the dates indicated below.

Name
   Title
   Date

 
 
 
 
 
/s/  RONALD J. TURNER      
Ronald J. Turner		   President, Chief Executive Officer and Director of TC PipeLines GP, Inc.
(Principal Executive Officer)		   December 22, 2004

/s/  RUSSELL K. GIRLING      
Russell K. Girling
 
Chief Financial Officer and Director of TC PipeLines GP, Inc.
(Principal Financial Officer)
 
December 22, 2004

/s/  AMY W. LEONG      
Amy W. Leong
 
Controller of TC PipeLines GP, Inc.
(Principal Accounting Officer)
 
December 22, 2004

/s/  ALBRECHT W.A. BELLSTEDT      
Albrecht W.A. Bellstedt
 
Director of TC PipeLines GP, Inc.
 
December 22, 2004

Kristine L. Delkus
 
Director of TC PipeLines GP, Inc.
 
 

/s/  JACK F. JENKINS-STARK      
Jack F. Jenkins-Stark
 
Director of TC PipeLines GP, Inc.
 
December 22, 2004

/s/  DAVID L. MARSHALL      
David L. Marshall
 
Director of TC PipeLines GP, Inc.
 
December 22, 2004

/s/  WALENTIN MIROSH      
Walentin Mirosh
 
Director of TC PipeLines GP, Inc.
 
December 22, 2004

II-5


EXHIBIT INDEX

Exhibit Number
   Description
*1.1           Form of Underwriting Agreement related to Common Units

*1.2        
 
Form of Underwriting Agreement related to Senior Debt

*1.3        
 
Form of Underwriting Agreement related to Subordinated Debt

*1.4        
 
Form of Sales Agreement

**4.1        
 
Form of certificate representing the Common Units of TC PipeLines, LP (filed as Exhibit A to Appendix A to TC PipeLines' Registration Statement on Form S-1 (Registration No. 333-69947) and incorporated by reference herein)

4.2        
 
Form of Senior Indenture

4.3        
 
Form of Subordinated Indenture

**4.4        
 
Amended and Restated Agreement of Limited Partnership of TC PipeLines, LP (incorporated by reference from Exhibit 3.1 to the Registrant's Form 10-K, File No. 000-26091, filed on March 28, 2000)

5.1        
 
Opinion of Andrews Kurth LLP as to the legality of the securities registered hereby

8.1        
 
Opinion of Andrews Kurth LLP as to tax matters

12.1        
 
Computation of ratio of earnings to fixed charges

23.1        
 
Consent of KPMG LLP (TC PipeLines, LP)

23.2        
 
Consent of KPMG LLP (Northern Border Pipeline Company)

23.3        
 
Consents of Andrews Kurth LLP (included in Exhibits 5.1 and 8.1)

24.1        
 
Power of Attorney (included on signature page)

*99.1        
 
Form T-1 Statement of Eligibility and Qualification related to the Senior Indenture and the Subordinated Indenture
*
To be filed by a post-effective amendment to this registration statement or as an exhibit to a Current Report on Form 8-K.

**
Incorporated by reference.



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TABLE OF CONTENTS
ABOUT THIS PROSPECTUS
WHERE YOU CAN FIND MORE INFORMATION
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS
ABOUT TC PIPELINES, LP
Ownership Chart
RISK FACTORS
USE OF PROCEEDS
RATIO OF EARNINGS TO FIXED CHARGES
DESCRIPTION OF COMMON UNITS
DESCRIPTION OF DEBT SECURITIES
TAX CONSIDERATIONS
INVESTMENT IN US BY EMPLOYEE BENEFIT PLANS
SELLING UNITHOLDERS
PLAN OF DISTRIBUTION
LEGAL
EXPERTS
PART II INFORMATION NOT REQUIRED IN PROSPECTUS
SIGNATURES
POWER OF ATTORNEY
EXHIBIT INDEX

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EXHIBIT 4.2

TC PIPELINES, LP,

ISSUER

AND

[                        ],

TRUSTEE

INDENTURE

Dated as of [            ] [    ], [            ]

SENIOR DEBT SECURITIES

TC PipeLines, LP

Reconciliation and Tie Between Trust Indenture Act of 1939, as amended, and Indenture, dated as of                        , 200    

Trust Indenture Act Section
   Indenture Section
§310   (a)(1)   609
    (a)(2)   609
    (a)(3)   Not Applicable
    (a)(4)   Not Applicable
    (b)   608; 610
§311   (a)   613
    (b)   613
§312   (a)   701; 702
    (b)   702
    (c)   702
§313   (a)   703
    (b)   *
    (c)   *
    (d)   703
§314   (a)   704
    (a)(4)   104; 1004
    (b)   Not Applicable
    (c)(1)   101
    (c)(2)   101; 102
    (c)(3)   Not Applicable
    (d)   Not Applicable
    (e)   102
§315   (a)   601
    (b)   602
    (c)   601
    (d)   601
    (e)   514
§316   (a)   101
    (a)(1) (A)   502; 512
    (a)(1) (B)   513
    (a)(2)   Not Applicable
    (b)   508
    (c)   104
§317   (a)(1)   503
    (a)(2)   504
    (b)   1003
§318   (a)   107

TABLE OF CONTENTS

 
    
   Page
ARTICLE I Definitions And Other Provisions Of General Application   1
  SECTION 101.   Definitions.   1
  SECTION 102.   Incorporation by Reference of Trust Indenture Act.   8
  SECTION 103.   Compliance Certificates and Opinions.   8
  SECTION 104.   Form of Documents Delivered to Trustee.   8
  SECTION 105.   Acts of Holders; Record Dates.   9
  SECTION 106.   Notices, Etc., to Trustee and Partnership.   10
  SECTION 107.   Notice to Holders; Waiver.   10
  SECTION 108.   Conflict with Trust Indenture Act.   10
  SECTION 109.   Effect of Headings and Table of Contents.   11
  SECTION 110.   Successors and Assigns.   11
  SECTION 111.   Separability Clause.   11
  SECTION 112.   Benefits of Indenture.   11
  SECTION 113.   Governing Law.   11
  SECTION 114.   Legal Holidays.   11
  SECTION 115.   Securities in a Composite Currency, Currency Unit or Foreign Currency.   11
  SECTION 116.   Judgment Currency.   12
  SECTION 117.   Language of Notices, Etc.   12
  SECTION 118.   Non-Recourse to the General Partner; No Personal Liability of Officers, Directors, Employees or Partners.   12
ARTICLE II Security Forms   12
  SECTION 201.   Forms Generally.   12
  SECTION 202.   Form of Face of Security.   13
  SECTION 203.   Form of Reverse of Security.   15
  SECTION 204.   Global Securities.   18
  SECTION 205.   Form of Trustee's Certificate of Authentication.   19
ARTICLE III The Securities   20
  SECTION 301.   Amount Unlimited; Issuable in Series.   20
  SECTION 302.   Denominations.   22
  SECTION 303.   Execution, Authentication, Delivery and Dating.   22
  SECTION 304.   Temporary Securities.   23
  SECTION 305.   Registration, Registration of Transfer and Exchange.   24
  SECTION 306.   Mutilated, Destroyed, Lost and Stolen Securities.   26
  SECTION 307.   Payment of Interest; Interest Rights Preserved.   26
  SECTION 308.   Persons Deemed Owners.   27
  SECTION 309.   Cancellation.   27
  SECTION 310.   Computation of Interest.   27
  SECTION 311.   CUSIP Numbers.   28
ARTICLE IV Satisfaction And Discharge   28
  SECTION 401.   Satisfaction and Discharge of Indenture.   28
  SECTION 402.   Application of Trust Money.   29
ARTICLE V Remedies   29
  SECTION 501.   Events of Default.   29
  SECTION 502.   Acceleration of Maturity; Rescission and Annulment.   29
  SECTION 503.   Collection of Indebtedness and Suits for Enforcement by Trustee.   30
  SECTION 504.   Trustee May File Proofs of Claim.   30
  SECTION 505.   Trustee May Enforce Claims Without Possession of Securities.   31
  SECTION 506.   Application of Money Collected.   31
  SECTION 507.   Limitation on Suits.   32
  SECTION 508.   Unconditional Right of Holders to Receive Principal, Premium and Interest.   32
  SECTION 509.   Restoration of Rights and Remedies.   32
  SECTION 510.   Rights and Remedies Cumulative.   32
  SECTION 511.   Delay or Omission Not Waiver.   32
  SECTION 512.   Control by Holders.   33
  SECTION 513.   Waiver of Past Defaults.   33
  SECTION 514.   Undertaking for Costs.   33
  SECTION 515.   Waiver of Usury, Stay or Extension Laws.   33
         

ii

ARTICLE VI The Trustee   34
  SECTION 601.   Certain Duties and Responsibilities.   34
  SECTION 602.   Notice of Defaults.   34
  SECTION 603.   Certain Rights of Trustee.   35
  SECTION 604.   Not Responsible for Recitals or Issuance of Securities.   36
  SECTION 605.   May Hold Securities.   36
  SECTION 606.   Money Held in Trust.   36
  SECTION 607.   Compensation and Reimbursement.   36
  SECTION 608.   Disqualification; Conflicting Interests.   37
  SECTION 609.   Corporate Trustee Required; Eligibility.   37
  SECTION 610.   Resignation and Removal; Appointment of Successor.   37
  SECTION 611.   Acceptance of Appointment by Successor.   38
  SECTION 612.   Merger, Conversion, Consolidation or Succession to Business.   39
  SECTION 613.   Preferential Collection of Claims Against Partnership.   39
  SECTION 614.   Appointment of Authenticating Agent.   39
ARTICLE VII Holders' Lists And Reports By Trustee And Partnership   40
  SECTION 701.   Partnership to Furnish Trustee Names and Addresses of Holders.   40
  SECTION 702.   Preservation of Information; Communications to Holders.   41
  SECTION 703.   Reports by Trustee.   42
  SECTION 704.   Reports by Partnership.   42
ARTICLE VIII Consolidation, Merger, Conveyance, Transfer Or Lease   42
  SECTION 801.   Partnership May Consolidate, Etc., Only on Certain Terms.   42
  SECTION 802.   Successor Substituted.   43
ARTICLE IX Supplemental Indentures   43
  SECTION 901.   Supplemental Indentures Without Consent of Holders.   43
  SECTION 902.   Supplemental Indentures with Consent of Holders.   44
  SECTION 903.   Execution of Supplemental Indentures.   45
  SECTION 904.   Effect of Supplemental Indentures.   45
  SECTION 905.   Conformity with Trust Indenture Act.   45
  SECTION 906.   Reference in Securities to Supplemental Indentures.   45
ARTICLE X Covenants   45
  SECTION 1001.   Payment of Principal, Premium and Interest.   45
  SECTION 1002.   Maintenance of Office or Agency.   45
  SECTION 1003.   Money for Securities Payments to Be Held in Trust.   46
  SECTION 1004.   Statement by Officers as to Default.   47
  SECTION 1005.   Existence.   47
  SECTION 1006.   Limitations on Liens.   47
  SECTION 1007.   Restriction of Sale-Leaseback Transaction.   48
  SECTION 1008.   Waiver of Certain Covenants.   49
  SECTION 1009.   Additional Amounts.   49
ARTICLE XI Redemption Of Securities    
  SECTION 1101.   Applicability of Article.   50
  SECTION 1102.   Election to Redeem; Notice to Trustee.   50
  SECTION 1103.   Selection by Trustee of Securities to be Redeemed.   50
  SECTION 1104.   Notice of Redemption.   50
  SECTION 1105.   Deposit of Redemption Price.   51
  SECTION 1106.   Securities Payable on Redemption Date.   51
  SECTION 1107.   Securities Redeemed in Part.   51
ARTICLE XII Sinking Funds   51
  SECTION 1201.   Applicability of Article.   51
  SECTION 1202.   Satisfaction of Sinking Fund Payments with Securities.   52
  SECTION 1203.   Redemption of Securities for Sinking Fund.   52
ARTICLE XIII Defeasance   52
  SECTION 1301.   Applicability of Article.   52
  SECTION 1302.   Legal Defeasance.   52
  SECTION 1303.   Covenant Defeasance.   53
  SECTION 1304.   Application by Trustee of Funds Deposited for Payment of Securities.   55
  SECTION 1305.   Repayment to Partnership.   55

iii

INDENTURE

Parties:

        INDENTURE, dated as of [            ] [    ], [            ], between TC PIPELINES, LP, a Delaware limited partnership (herein called the "Partnership"), having its principal office at 110 Turnpike Road, Suite 203, Westborough, Massachusetts 01581 and [                        ], as trustee (herein called the "Trustee").

Recitals Of The Partnership:

        The Partnership has duly authorized the execution and delivery of this Indenture to provide for the issuance from time to time of its unsecured senior debentures, notes or other evidences of indebtedness (herein called the "Securities"), to be issued in one or more series as in this Indenture provided.

        All things necessary to make this Indenture a valid agreement of the Partnership, in accordance with its terms, have been done.

        This Indenture is subject to the provisions of the Trust Indenture Act that are required to be a part of this Indenture and, to the extent applicable, shall be governed by such provisions.

        NOW, THEREFORE, THIS INDENTURE WITNESSETH:

        For and in consideration of the premises and the purchase of the Securities by the Holders thereof, it is mutually covenanted and agreed, for the equal and proportionate benefit of all Holders of the Securities or of series thereof, as follows:

ARTICLE I
DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

SECTION 101. Definitions.

        For all purposes of this Indenture, except as otherwise expressly provided or unless the context otherwise requires:

        Certain terms, used principally in Article VI, are defined in that Article.

        "Act," when used with respect to any Holder, has the meaning specified in Section 105.

        "Affiliate" of any specified Person means any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such specified Person. For the purposes of this definition, "control" when used with respect to any specified Person means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise, and the terms "controlling" and "controlled" have meanings correlative to the foregoing.


        "Authenticating Agent" means any Person authorized by the Trustee to act on behalf of the Trustee to authenticate Securities.

        "Banking Day" means, with respect to any city, any date on which commercial banks are open for business in that city.

        "Bankruptcy Law" means Title 11, U.S. Code, or any similar federal or state law for the relief of debtors or the protection of creditors.

        "Board of Directors" means the board of directors of the General Partner, or the executive or any other committee of that board duly authorized to act in respect thereof. If the Partnership shall change its form of entity to other than a limited partnership, the references to officers or the Board of Directors of the General Partner shall mean the officers or the Board of Directors (or other comparable governing body), respectively, of the Partnership.

        "Board Resolution" means a copy of a resolution certified by the Secretary or an Assistant Secretary of the General Partner, the principal financial officer of the General Partner or any other authorized officer of the General Partner or a person duly authorized by any of them, to have been duly adopted by the Board of Directors and to be in full force and effect on the date of such certification, and delivered to the Trustee. Where any provision of this Indenture refers to action to be taken pursuant to a Board Resolution (including the establishment of any series of the Securities and the forms and terms thereof), such action may be taken by any committee, officer or employee of the Partnership authorized to take such action by the Board of Directors as evidenced by a Board Resolution.

        "Business Day," when used with respect to any Place of Payment or other location, means, except as otherwise provided as contemplated by Section 301 with respect to any series of Securities, each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in that Place of Payment or other location are authorized or obligated by law, executive order or regulation to close.

        "Capital Interests" means any and all shares, interests, participations, rights or other equivalents (however designated) of capital stock, including, without limitation, with respect to partnerships, partnership interests (whether general or limited) and any other interest or participation that confers on a Person the right to receive a share of the profits and losses of, or distributions of assets of, such partnership.

        "Commission" means the Securities and Exchange Commission, as from time to time constituted, created under the Exchange Act or, if at any time after the execution of this instrument such Commission is not existing and performing the duties now assigned to it under the Trust Indenture Act, then the body performing such duties at such time.

        "Consolidated Net Tangible Assets" means, at any date of determination, all consolidated assets after deducting therefrom (a) all current liabilities (excluding (i) any current liabilities renewable or extendable at the option of the obligor to a time more than 12 months after the time as of which the amount thereof is being computed, and (ii) current maturities of long-term debt), and (b) the value (net of any applicable reserves) of all goodwill, trade names, trademarks, patents, unamortized debt discount and expense and other like intangibles, all as set forth on the consolidated balance sheet of the Partnership and its consolidated Subsidiaries for the Partnership's most recently completed fiscal quarter, prepared in accordance with GAAP.

        "Corporate Trust Office" means the office of the Trustee at which at any particular time its corporate trust business shall be principally administered in [                        ], and which, at the date hereof is [                        ].

        "corporation" includes corporations, associations, limited liability companies, joint-stock companies and business trusts.

        "covenant defeasance" has the meaning specified in Section 1303.

        "CUSIP" means the Committee on Uniform Securities Identification Procedures.

        "Custodian" means any receiver, trustee, assignee, liquidator or similar official under any Bankruptcy Law.

        "Debt" means any obligation created or assumed by any Person for the repayment of money borrowed, and any Purchase Money Obligation created or assumed by such Person.

2


        "Default" means, with respect to a series of Securities, any event that is, or after notice or lapse of time or both would be, an Event of Default.

        "Defaulted Interest" has the meaning specified in Section 307.

        "defeasance" has the meaning specified in Section 1302.

        "Definitive Security" means a Security other than a Global Security or a temporary Security.

        "Depositary" means, with respect to Securities of any series issuable or issued in whole or in part in the form of one or more Global Securities, a clearing agency registered under the Exchange Act that is designated to act as Depositary for such Securities as contemplated by Section 301, until a successor Depositary shall have become such pursuant to the applicable provisions of this Indenture, and thereafter shall mean or include each Person which is then a Depositary hereunder, and if at any time there is more than one such Person, shall be a collective reference to such Persons.

        "Dollar" or "$" means the coin or currency of the United States of America as at the time of payment is legal tender for the payment of public and private debts.

        "Event of Default" has the meaning specified in Section 501.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended from time to time, and any statute successor thereto.

        "Foreign Currency" means a currency used by the government of a country other than the United States of America.

        "GAAP" means generally accepted accounting principles in the United States set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other entity as may be approved by a significant segment of the accounting profession of the United States, as in effect from time to time.

        "General Partner" means the person serving as such under the Partnership Agreement, which, on the date hereof, is TC PipeLines GP, Inc., a Delaware corporation.

        "Global Security" means a Security in global form that evidences all or part of a series of Securities and is authenticated and delivered to, and registered in the name of, the Depositary for the Securities of such series or its nominee.

        "Holder" means a Person in whose name a Security is registered in the Security Register.

        "Indenture" means this instrument as originally executed or as it may from time to time be supplemented or amended by one or more indentures supplemental hereto entered into pursuant to the applicable provisions hereof, including, for all purposes of this instrument, and any such supplemental indenture, the provisions of the Trust Indenture Act that are deemed to be a part of and govern this instrument and any such supplemental indenture, respectively. The term "Indenture" also shall include the terms of particular series of Securities established as contemplated by Section 301.

        "interest," when used with respect to an Original Issue Discount Security which by its terms bears interest only after Maturity, means interest payable after Maturity.

        "Interest Payment Date," when used with respect to any Security, means the Stated Maturity of an installment of interest on such Security.

        "Issue Date" means, with respect to any series of Debt Securities issued under this Indenture, the date on which Debt Securities of that series are initially issued.

        "Lien" means any mortgage, pledge, security interest, charge, lien or other encumbrance of any kind, whether or not filed, recorded and perfected under applicable law which secures payment or performance of any obligation.

        "mandatory sinking fund payment" has the meaning specified in Section 1201.

3


        "Maturity," when used with respect to any Security, means the date on which the principal of such Security or an installment of principal becomes due and payable as therein or herein provided, whether at the Stated Maturity or by declaration of acceleration, call for redemption or otherwise.

        "Non-Recourse Debt" means any Debt (other than endorsements for collection in the ordinary course of business) in respect of obligations of another Person incurred or assumed to finance or refinance the creation, development, construction or acquisition of assets and any increases in or extensions, renewals or refunding of any such Debt, provided that the recourse of the lender thereof or any agent, trustee, receiver or other Person acting on behalf of the lender in respect of such Debt or any judgment in respect thereof is limited in all circumstances (other than in respect of false or misleading representations or warranties and customary indemnities provided with respect to such financings) to the assets created, developed, constructed, or acquired with respect to which such Debt has been incurred or assumed and to any receivables, inventory, equipment, chattel paper, intangibles and other rights or collateral arising from or connected with the assets created, developed, constructed or acquired (and, for certainty, shall include the shares or other ownership interests of a single purpose entity (or any parent thereof) which holds only such assets and other rights and collateral arising from or connected therewith) and to which the lender has recourse.

        "Notice of Default" means a written notice of the kind specified in Section 501(3).

        "Officers' Certificate" means a certificate signed by any two officers of the General Partner(or if the Partnership shall change its form of entity to other than a limited partnership, by Persons or officers, members, agents and the like positions comparable to those of the foregoing nature, as applicable), and delivered to the Trustee. One of the officers or such other Persons (as applicable) signing an Officers' Certificate given pursuant to Section 1004 shall be the principal executive, financial or accounting officer of the General Partner (or if the Partnership shall change its form of entity to other than a limited partnership, by Persons or officers, members, agents and the like positions comparable to those of the foregoing nature, as applicable).

        "Opinion of Counsel" means a written opinion of counsel, who may be an employee of or counsel for the Partnership, the General Partner or an Affiliate of the General Partner and who shall be reasonably acceptable to the trustee.

        "Original Issue Discount Security" means any Security which provides for an amount less than the stated principal amount thereof to be due and payable upon a declaration of acceleration of the Maturity thereof pursuant to Section 502.

        "Outstanding," when used with respect to Securities, means, as of the date of determination, all Securities theretofore authenticated and delivered under this Indenture, except:

provided, however, that in determining whether the Holders of the requisite principal amount of the Outstanding Securities have given any request, demand, authorization, direction, notice, consent or waiver hereunder,

4

(A) the principal amount of an Original Issue Discount Security that shall be deemed to be Outstanding shall be the amount of the principal thereof that would be due and payable as of the date of such determination upon acceleration of the Maturity thereof on such date pursuant to Section 502, (B) the principal amount of a Security denominated in one or more currencies or currency units other than U.S. dollars shall be the U.S. dollar equivalent of such currencies or currency units, determined in the manner provided as contemplated by Section 301 on the date of original issuance of such Security or by Section 115, if not otherwise so provided pursuant to Section 301, of the principal amount (or, in the case of an Original Issue Discount Security, the U.S. dollar equivalent (as so determined) on the date of original issuance of such Security, of the amount determined as provided in clause (A) above) of such Security, and (C) Securities owned by the Partnership or any other obligor upon the Securities or any Affiliate of the Partnership or of such other obligor shall be disregarded and deemed not to be Outstanding, except that, in determining whether the Trustee shall be protected in relying upon any such request, demand, authorization, direction, notice, consent or waiver, only Securities which the Trustee knows to be so owned shall be so disregarded. Securities so owned as described in clause (C) of the immediately preceding sentence which have been pledged in good faith may be regarded as Outstanding if the pledgee establishes to the satisfaction of the Trustee the pledgee's right so to act with respect to such Securities and that the pledgee is not the Partnership or any other obligor upon the Securities or any Affiliate of the Partnership or of such other obligor.

        "Pari Passu Debt" means any Debt of the Partnership, whether outstanding on the Issue Date or thereafter created, incurred or assumed, unless, in the case of any particular Debt, the instrument creating or evidencing the same or pursuant to which the same is outstanding expressly provides that such Debt shall be subordinated in right of payment to the Securities.

        "Partnership" means the Person named as the "Partnership" in the first paragraph of this instrument until a successor Person shall have become such pursuant to the applicable provisions of this Indenture, and thereafter "Partnership" shall mean such successor Person.

        "Partnership Agreement" means the Agreement of Limited Partnership of the Partnership as in effect from time to time.

        "Partnership Request" or "Partnership Order" means a written request or order delivered to the Trustee and signed in the name of the Partnership by any two officers of the General Partner, or if the Partnership shall change its form of entity to other than a limited partnership, by Persons or officers, members, agents and the like positions comparable to those of the foregoing nature, as applicable.

        "Paying Agent" means any Person authorized by the Partnership to pay the principal of and any premium or interest on any Securities on behalf of the Partnership.

        "Periodic Offering" means an offering of Securities of a series from time to time, the specific terms of which Securities, including, without limitation, the rate or rates of interest or formula for determining the rate or rates of interest thereon, if any, the Stated Maturity or Stated Maturities thereof, the original issue date or dates thereof, the redemption provisions, if any, with respect thereto, and any other terms specified as contemplated by Section 301 with respect thereto, are to be determined by the Partnership upon the issuance of such Securities.

        "Permitted Liens" means, with respect to any Person:

5

        "Person" means any individual, corporation, partnership, joint venture, limited liability company, association, joint-stock company, trust, other entity, unincorporated organization or government, or any agency or political subdivision thereof.

        "Place of Payment," when used with respect to the Securities of any series, means, unless otherwise specifically provided for with respect to such series as contemplated by Section 301, the office or agency of the Partnership in The City of New York and such other place or places where, subject to the provisions of Section 1002, the principal of and any premium and interest on the Securities of that series are payable as contemplated by Section 301.

        "Predecessor Security" of any particular Security means every previous Security evidencing all or a portion of the same Debt as that evidenced by such particular Security; and, for the purposes of this definition, any Security authenticated and delivered under Section 306 in exchange for or in lieu of a mutilated, destroyed, lost or stolen Security shall be deemed to evidence the same debt as the mutilated, destroyed, lost or stolen Security.

        "Purchase Money Obligations" means any monetary obligation of the Partnership or of any of its Subsidiaries created or assumed as part of the purchase price of real or tangible personal property, an any other property (including intangible property) related to such real or intangible property whether or not secured, and

6


any extensions, renewals or refunding of any such obligation, provided that the principal amount of such obligation outstanding on the date of such extension, renewal or refunding is not increased and further provided that any Lien given in respect of such obligation shall not extend to any property other than the property acquired in connection with which such obligation was created or assumed and fixed improvements, if any, erected or constructed thereon and the proceeds of such acquired property.

        "Redemption Date," when used with respect to any Security to be redeemed, means the date fixed for such redemption by or pursuant to this Indenture.

        "Redemption Price," when used with respect to any Security to be redeemed, means the price at which it is to be redeemed pursuant to this Indenture.

        "Regular Record Date" for the interest payable on any Interest Payment Date on the Securities of any series means the date specified for that purpose as contemplated by Section 301.

        "Responsible Officer," when used with respect to the Trustee, means any officer of the Trustee within the corporate trust department, including any Vice President, assistant secretary, assistant treasurer, assistant cashier, trust officer, assistant trust officer or assistant controller assigned to the Corporate Trust Office, or any other officer of the Trustee customarily performing functions similar to those performed by any of the above designated officers and also means, with respect to a particular corporate trust matter, any other officer of the Trustee to whom such matter is referred because of his knowledge of and familiarity with the particular subject, and who shall have direct responsibility for the administration of this Indenture.

        "Sale-Leaseback Transaction" means the sale or transfer by the Partnership or any of its Subsidiaries of any property or assets to a Person (other than the Partnership or a Subsidiary of the Partnership) and the taking back by the Partnership or any Subsidiary of the Partnership, as the case may be, of a lease of such property or assets.

        "Securities" has the meaning stated in the first recital of this Indenture and more particularly means any Securities authenticated and delivered under this Indenture.

        "Security Register" and "Security Registrar" have the respective meanings specified in Section 305.

        "Special Record Date" for the payment of any Defaulted Interest means a date fixed by the Trustee pursuant to Section 307.

        "Stated Maturity," when used with respect to any Security or any installment of principal thereof or interest thereon, means the date specified in such Security as the fixed date on which the principal of such Security or such installment of principal or interest is due and payable.

        "Subsidiary" of any Person means (i) any partnership of which more than 50% of the Capital Interests (considering all partners' Capital Interests as a single class) is at the time owned or controlled, directly or indirectly, by such Person or one or more of the other Subsidiaries of such Person or combination thereof, or (ii) any corporation, association or other business entity of which more than 50% of the total voting power of the Capital Interests entitled (without regard to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof is at the time owned or controlled, directly or indirectly, by such Person or one or more of the other Subsidiaries of such Person or combination thereof.

        "Trust Indenture Act" means the Trust Indenture Act of 1939 as in force at the date as of which this instrument was executed, except as otherwise provided in Section 905; provided, however, that if the Trust Indenture Act of 1939 is amended after such date, "Trust Indenture Act" means, to the extent required by any such amendment, the Trust Indenture Act of 1939 as so amended.

        "Trustee" means the Person named as the "Trustee" in the first paragraph of this instrument until a successor Trustee shall have become such pursuant to the applicable provisions of this Indenture, and thereafter "Trustee" shall mean or include each Person who is then a Trustee hereunder, and if at any time there is more than one such Person, "Trustee" as used with respect to the Securities of any series shall mean each Trustee with respect to Securities of that series.

        "U.S. Government Obligations" means securities which are (i) direct obligations of the United States for the payment of which its full faith and credit is pledged, or (ii) obligations of a Person controlled or supervised

7


by and acting as an agency or instrumentality of the United States, the payment of which is unconditionally guaranteed as a full faith and credit obligation by the United States, each of which are not callable or redeemable at the option of the issuer thereof.

        "Vice President," when used with respect to the Partnership, means any vice president of the General Partner, or when used with respect to the Trustee, means any vice president of the Trustee.

SECTION 102. Incorporation by Reference of Trust Indenture Act.

        Whenever this Indenture refers to a provision of the Trust Indenture Act, the provision is incorporated by reference in and made a part of this Indenture. The following Trust Indenture Act terms used in this Indenture have the following meanings:

        "commission" means the Commission.

        "indenture securities" means the Securities.

        "indenture security holder" means a Holder.

        "indenture to be qualified" means this Indenture.

        "indenture trustee" or "institutional trustee" means the Trustee.

        "obligor" on the indenture securities means the Partnership or any other obligor on the indenture securities.

        All terms used in this Indenture that are defined by the Trust Indenture Act, defined by a Trust Indenture Act reference to another statute or defined by a Commission rule under the Trust Indenture Act have the meanings so assigned to them.

SECTION 103. Compliance Certificates and Opinions.

        Upon any application or request by the Partnership to the Trustee to take any action under any provision of this Indenture, the Partnership shall furnish to the Trustee an Officers' Certificate stating that all conditions precedent, if any, provided for in this Indenture relating to the proposed action have been complied with and an Opinion of Counsel stating that in the opinion of such counsel all such conditions precedent, if any, have been complied with, except that in the case of any such application or request as to which the furnishing of such documents is specifically required by any provision of this Indenture relating to such particular application or request, no additional certificate or opinion need be furnished except as required under Section 314(c) of the Trust Indenture Act.

        Every certificate or opinion with respect to compliance with a condition or covenant provided for in this Indenture (except for certificates provided for in Section 1004) shall include:

SECTION 104. Form of Documents Delivered to Trustee.

        In any case where several matters are required to be certified by, or covered by an opinion of, any specified Person, it is not necessary that all such matters be certified by, or covered by the opinion of, only one such Person, or that they be so certified or covered by only one document, but one such Person may certify or give an

8


opinion with respect to some matters and one or more other such Persons as to other matters, and any such Person may certify or give an opinion as to such matters in one or several documents.

        Any certificate or opinion of an officer of the Partnership or the General Partner may be based, insofar as it relates to legal matters, upon a certificate or opinion of, or representations by, counsel, unless such officer knows, or in the exercise of reasonable care should know, that the certificate or opinion or representations with respect to the matters upon which his certificate or opinion is based are erroneous. Any such certificate or opinion of counsel may be based, insofar as it relates to factual matters, upon a certificate or opinion of, or representations by, an officer or officers of the Partnership or the General Partner stating that the information with respect to such factual matters is in the possession of the Partnership or the General Partner, unless such counsel knows that the certificate or opinion or representations with respect to such matters are erroneous.

        Where any Person is required to make, give or execute two or more applications, requests, consents, certificates, statements, opinions or other instruments under this Indenture, they may, but need not, be consolidated and form one instrument.

SECTION 105. Acts of Holders; Record Dates.

        Any request, demand, authorization, direction, notice, consent, waiver or other action provided or permitted by this Indenture to be given or taken by Holders may be embodied in and evidenced by one or more instruments of substantially similar tenor signed (either physically or by means of a facsimile or an electronic transmission, provided that such electronic transmission is transmitted through the facilities of a Depositary) by such Holders in person or by an agent duly appointed in writing; and, except as herein otherwise expressly provided, such action shall become effective when such instrument or instruments are delivered (either physically or by means of a facsimile or an electronic transmission, provided that such electronic transmission is transmitted through the facilities of a Depositary) to the Trustee and, where it is hereby expressly required, to the Partnership. Such instrument or instruments (and the action embodied therein and evidenced thereby) are herein sometimes referred to as the "Act" of the Holders signing such instrument or instruments. Proof of execution of any such instrument or of a writing appointing any such agent shall be sufficient for any purpose of this Indenture and (subject to Section 315 of the Trust Indenture Act) conclusive in favor of the Trustee and the Partnership, if made in the manner provided in this Section 105.

        The fact and date of the execution by any Person of any such instrument or writing may be proved by the affidavit of a witness of such execution or by a certificate of a notary public or other officer authorized by law to take acknowledgments of deeds, certifying that the individual signing such instrument or writing acknowledged to him the execution thereof. Where such execution is by a signer acting in a capacity other than his individual capacity, such certificate or affidavit shall also constitute sufficient proof of his authority. The fact and date of the execution of any such instrument or writing, or the authority of the Person executing the same, may also be proved in any other manner which the Trustee deems sufficient.

        The ownership, principal amount and serial numbers of Securities held by any Person, and the date of commencement of such Person's holding the same, shall be proved by the Security Register.

        Any request, demand, authorization, direction, notice, consent, waiver or other action of the Holder of any Security shall bind every future Holder of the same Security and the Holder of every Security issued upon the registration of transfer thereof or in exchange therefor or in lieu thereof in respect of anything done, omitted or suffered to be done by the Trustee or the Partnership in reliance thereon, regardless of whether notation of such action is made upon such Security.

        Without limiting the foregoing, a Holder entitled hereunder to give or take any action hereunder with regard to any particular Security may do so with regard to all or any part of the principal amount of such Security or by one or more duly appointed agents each of which may do so pursuant to such appointment with regard to all or any different part of such principal amount.

        The Partnership may set any day as the record date for the purpose of determining the Holders of Outstanding Securities of any series entitled to give or take any request, demand, authorization, direction, notice, consent, waiver or other action provided or permitted by this Indenture to be given or taken by Holders of Securities of such series, but the Partnership shall have no obligation to do so. With regard to any record date

9


set pursuant to this paragraph, the Holders of Outstanding Securities of the relevant series on such record date (or their duly appointed agents), and only such Persons, shall be entitled to give or take the relevant action, regardless of whether such Holders remain Holders after such record date.

SECTION 106. Notices, Etc., to Trustee and Partnership.

        Any request, demand, authorization, direction, notice, consent, waiver or Act of Holders or other document provided or permitted by this Indenture to be made upon, given or furnished to, or filed with,

SECTION 107. Notice to Holders; Waiver.

        Where this Indenture provides for notice to Holders of any event, such notice shall be sufficiently given (unless otherwise herein expressly provided) if in writing and mailed, first-class postage prepaid (if international mail, by air mail), to each Holder affected by such event, at his address as it appears in the Security Register, not later than the latest date (if any), and not earlier than the earliest date (if any), prescribed for the giving of such notice. In any case where notice to Holders is given by mail, neither the failure to mail such notice, nor any defect in any notice so mailed, to any particular Holder shall affect the sufficiency of such notice with respect to other Holders. Any notice mailed to a Holder in the manner herein prescribed shall be conclusively deemed to have been received by such Holder, whether or not such Holder actually receives such notice.

        Where this Indenture provides for notice in any manner, such notice may be waived in writing by the Person entitled to receive such notice, either before or after the event, and such waiver shall be the equivalent of such notice. Waivers of notice by Holders shall be filed with the Trustee, but such filing shall not be a condition precedent to the validity of any action taken in reliance upon such waiver.

        In case by reason of the suspension of regular mail service or by reason of any other cause it shall be impracticable to give such notice by mail, then such notification as shall be made with the approval of the Trustee shall constitute a sufficient notification for every purpose hereunder.

SECTION 108. Conflict with Trust Indenture Act.

        If any provision hereof limits, qualifies or conflicts with a provision of the Trust Indenture Act that is required under such Act to be a part of and govern this Indenture, the latter provision shall control. If any provision of this Indenture modifies or excludes any provision of the Trust Indenture Act that may be so modified or excluded, the latter provision shall be deemed to apply to this Indenture as so modified or excluded, as the case may be.

10

SECTION 109. Effect of Headings and Table of Contents.

        The Article and Section headings herein and the Table of Contents are for convenience only and shall not affect the construction hereof.

SECTION 110. Successors and Assigns.

        All covenants and agreements in this Indenture by the Partnership shall bind its successors and assigns, whether so expressed or not.

SECTION 111. Separability Clause.

        In case any provision in this Indenture or in the Securities shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

SECTION 112. Benefits of Indenture.

        Nothing in this Indenture or in the Securities, express or implied, shall give to any Person, other than the parties hereto and their successors hereunder and the Holders, any benefit or any legal or equitable right, remedy or claim under this Indenture.

SECTION 113. Governing Law.

        This Indenture and the Securities shall be governed by and construed in accordance with the laws of the State of New York.

SECTION 114. Legal Holidays.

        In any case where any Interest Payment Date, Redemption Date or Stated Maturity of any Security shall not be a Business Day at any Place of Payment, then (notwithstanding any other provision of this Indenture or of the Securities (other than a provision of the Securities of any series that specifically states that such provision shall apply in lieu of this Section 114)) payment of interest or principal (and any premium) need not be made at such Place of Payment on such date, but may be made on the next succeeding Business Day at such Place of Payment with the same force and effect as if made on the Interest Payment Date or Redemption Date, or at the Stated Maturity, provided that no interest shall accrue for the period from and after such Interest Payment Date, Redemption Date or Stated Maturity, as the case may be.

SECTION 115. Securities in a Composite Currency, Currency Unit or Foreign Currency.

        Unless otherwise specified in an Officer's Certificate delivered pursuant to Section 301 of this Indenture with respect to a particular series of Securities, whenever for purposes of this Indenture any action may be taken by the Holders of a specified percentage in aggregate principal amount of Securities of all series or all series affected by a particular action at the time Outstanding and, at such time, there are Outstanding Securities of any series which are denominated in a coin, currency or currencies other than Dollars (including, but not limited to, any composite currency, currency units or Foreign Currency), then the principal amount of Securities of such series which shall be deemed to be Outstanding for the purpose of taking such action shall be that amount of Dollars that could be obtained for such amount at the Market Exchange Rate. For purposes of this Section 115, the term "Market Exchange Rate" shall mean the noon Dollar buying rate in The City of New York for cable transfers of such currency or currencies as published by the Federal Reserve Bank of New York, as of the most recent available date. If such Market Exchange Rate is not so available for any reason with respect to such currency, the Trustee shall use, in its sole discretion and without liability on its part, such quotation of the Federal Reserve Bank of New York as of the most recent available date, or quotations or rates of exchange from one or more major banks in The City of New York or in the country of issue of the currency in question, which for purposes of euros shall be Brussels, Belgium, or such other quotations or rates of exchange as the Trustee shall deem appropriate. The provisions of this paragraph shall apply in determining the equivalent principal

11


amount in respect of Securities of a series denominated in a currency other than Dollars in connection with any action taken by Holders of Securities pursuant to the terms of this Indenture.

        All decisions and determinations of the Trustee regarding the Market Exchange Rate or any alternative determination provided for in the preceding paragraph shall be in its sole discretion and shall, in the absence of manifest error, be conclusive to the extent permitted by law for all purposes and irrevocably binding upon the Issuer and all Holders.

SECTION 116. Judgment Currency.

        The Company agrees, to the fullest extent that it may effectively do so under applicable law, that (a) if for the purpose of obtaining judgment in any court it is necessary to convert the sum due in respect of the principal of or interest on the Securities of any series (the "Required Currency") into a currency in which a judgment will be rendered (the "Judgment Currency"), the rate of exchange used shall be the rate at which in accordance with normal banking procedures the Trustee could purchase in The City of New York the Required Currency with the Judgment Currency on the day on which final unappealable judgment is entered, unless such day is not a Banking Day, then, to the extent permitted by applicable law, the rate of exchange used shall be the rate at which in accordance with normal banking procedures the Trustee could purchase in The City of New York the Required Currency with the Judgment Currency on the Banking Day next preceding the day on which final unappealable judgment is entered and (b) its obligations under this Indenture to make payments in the Required Currency (i) shall not be discharged or satisfied by any tender, or any recovery pursuant to any judgment (whether or not entered in accordance with subsection (a)), in any currency other than the Required Currency, except to the extent that such tender or recovery shall result in the actual receipt, by the payee, of the full amount of the Required Currency expressed to be payable in respect of such payments, (ii) shall be enforceable as an alternative or additional cause of action for the purpose of recovering in the Required Currency the amount, if any, by which such actual receipt shall fall short of the full amount of the Required Currency so expressed to be payable and (iii) shall not be affected by judgment being obtained for any other sum due under this Indenture.

SECTION 117. Language of Notices, Etc.

        Any request, demand, authorization, direction, notice, consent, waiver or Act required or permitted under this Indenture shall be in the English language, except that any published notice may be in an official language of the country of publication.

SECTION 118. Non-Recourse to the General Partner; No Personal Liability of Officers, Directors, Employees or Partners.

        Obligations of the Partnership under this Indenture and the Securities hereunder are non-recourse to the General Partner, and its Affiliates (other than the Partnership), and payable only out of cash flow and assets of the Partnership. The Trustee, and each Holder of a Security by its acceptance thereof, will be deemed to have agreed in this Indenture that (1) neither the General Partner nor its assets (nor any of its Affiliates other than the Partnership, nor their respective assets) shall be liable for any of the obligations of the Partnership under this Indenture or such Securities, and (2) no director, officer, employee, stockholder or unitholder, as such, of the Partnership, the Trustee, the General Partners or any Affiliate of any of the foregoing entities shall have any personal liability in respect of the obligations of the Partnership under this Indenture or such Securities by reason of his, her or its status.

ARTICLE II
SECURITY FORMS

SECTION 201. Forms Generally.

        The Securities of each series shall be in substantially the form set forth in this Article II, or in such other form or forms as shall be established by or pursuant to a Board Resolution or in one or more indentures supplemental hereto, in each case with such appropriate insertions, omissions, substitutions and other variations

12


as are required or permitted by this Indenture, and may have such letters, numbers or other marks of identification and such legends or endorsements placed thereon as may be required to comply with the rules of any securities exchange or automated quotation system on which the Securities of such series may be listed or traded or Depositary therefor or as may, consistently herewith, be determined by the officers executing such Securities, as evidenced by their execution of the Securities. If the form of Securities of any series is established by action taken pursuant to a Board Resolution, a copy of an appropriate record of such action shall be certified by an authorized officer or other authorized Person on behalf of the Partnership and delivered to the Trustee at or prior to the delivery of the Partnership Order contemplated by Section 303 for the authentication and delivery of such Securities.

        The definitive Securities shall be printed, lithographed or engraved on steel engraved borders or may be produced in any other manner, all as determined by the officers executing such Securities, as evidenced by their execution of such Securities.

        The forms of Global Securities of any series shall have such provisions and legends as are customary for Securities of such series in global form, including without limitation any legend required by the Depositary for the Securities of such series.

SECTION 202. Form of Face of Security.

        [If the Security is an Original Issue Discount Security, insert — FOR PURPOSES OF SECTION 1275 OF THE UNITED STATES INTERNAL REVENUE CODE OF 1986, AS AMENDED, THE AMOUNT OF THE ORIGINAL ISSUE DISCOUNT IS. .. .. .. ., THE ISSUE DATE IS. .. .. ., 20.. . [AND] [,] THE YIELD TO MATURITY IS. .. .. .. . [,] [AND THE ORIGINAL ISSUE DISCOUNT FOR THE SHORT ACCRUAL PERIOD IS. .. .. .. . AND THE METHOD USED TO DETERMINE THE YIELD THEREFOR IS. .. ..]]

        [Insert any other legend required by the United States Internal Revenue Code and the regulations thereunder.]

        [If a Global Security, insert legend required by Section 204 of the Indenture.]

        [If applicable, insert — UNLESS THIS SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION, TO THE PARTNERSHIP OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY SECURITY ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]

TC PipeLines, LP
[TITLE OF SECURITY]

No.                           U.S. $                        

[CUSIP No. [                        ]]
 
 

        TC PIPELINES, LP, a Delaware limited partnership (herein called the "Partnership," which term includes any successor Person under the Indenture hereinafter referred to), for value received, hereby promises to pay to                        , or registered assigns, the principal sum of                        United States Dollars on                        [if the Security is to bear interest prior to Maturity, insert — , and to pay interest thereon from                        , or from the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually on                and                in each year, commencing                 ,            , at the rate of    % per annum, until the principal hereof is paid or made available for payment [if applicable, insert — , and at the rate of    % per annum on any overdue principal and premium and on any overdue installment of interest]. [If applicable, insert — The amount of interest payable for any period shall be computed on the basis of twelve 30-day months and a 360-day year. The amount of interest payable for any partial period shall be computed on the basis of a

13


360-day year of twelve 30-day months and the days elapsed in any partial month. In the event that any date on which interest is payable on this Security is not a Business Day, then a payment of the interest payable on such date will be made on the next succeeding day which is a Business Day (and without any interest or other payment in respect of any such delay) with the same force and effect as if made on the date the payment was originally payable. A "Business Day" shall mean, when used with respect to any Place of Payment, each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in that Place of Payment are authorized or obligated by law, executive order or regulation to close.] The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in such Indenture, be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on the Regular Record Date for such interest, which shall be the                or                (whether or not a Business Day), as the case may be, next preceding such Interest Payment Date. Any such interest not so punctually paid or duly provided for shall forthwith cease to be payable to the Holder on such Regular Record Date and may either be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of Securities of this series not less than 10 days prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange or automated quotation system on which the Securities of this series may be listed or traded, and upon such notice as may be required by such exchange or automated quotation system, all as more fully provided in such Indenture].

        [If the Security is not to bear interest prior to Maturity, insert — The principal of this Security shall not bear interest except in the case of a default in payment of principal upon acceleration, upon redemption or at Stated Maturity and in such case the overdue principal of this Security shall bear interest at the rate of    % per annum (to the extent that the payment of such interest shall be legally enforceable), which shall accrue from the date of such default in payment to the date payment of such principal has been made or duly provided for. Interest on any overdue principal shall be payable on demand. Any such interest on any overdue principal that is not so paid on demand shall bear interest at the rate of    % per annum (to the extent that the payment of such interest shall be legally enforceable), which shall accrue from the date of such demand for payment to the date payment of such interest has been made or duly provided for, and such interest shall also be payable on demand.]

        [If a Global Security, insert — Payment of the principal of [(and premium, if any)] and [if applicable, insert — any such] interest on this Security will be made by transfer of immediately available funds to a bank account in                        designated by the Holder in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts [state other currency].]

        [If a Definitive Security, insert — Payment of the principal of [(and premium, if any)] and [if applicable, insert — any such] interest on this Security will be made at the office or agency of the Partnership maintained for that purpose in                        , [in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts] [state other currency] [or subject to any laws or regulations applicable thereto and to the right of the Partnership (as provided in the Indenture) to rescind the designation of any such Paying Agent, at the [main] offices of                        in                         and                         in                        , or at such other offices or agencies as the Partnership may designate, by [United States Dollar] [state other currency] check drawn on, or transfer to a [United States Dollar] account maintained by the payee with, a bank in The City of New York (so long as the applicable Paying Agent has received proper transfer instructions in writing at least [    ] days prior to the payment date)] [if applicable, insert — ; provided, however, that payment of interest may be made at the option of the Partnership by [United States Dollar] [state other currency] check mailed to the addresses of the Persons entitled thereto as such addresses shall appear in the Security Register] [or by transfer to a [United States Dollar] [state other currency] account maintained by the payee with a bank in The City of New York [state other Place of Payment] (so long as the applicable Paying Agent has received proper transfer instructions in writing by the Record Date prior to the applicable Interest Payment Date)].]

        Reference is hereby made to the further provisions of this Security set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

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        Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof by manual signature, this Security shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

        IN WITNESS WHEREOF, the Partnership has caused this instrument to be duly executed.

Dated:                        

    TC PIPELINES, LP,

 
 
By:
TC PipeLines GP, Inc.
Its General Partner

 
 
By:

 
 
Name:

 
 
Title:

SECTION 203. Form of Reverse of Security.

        This Security is one of a duly authorized issue of senior securities of the Partnership (herein called the "Securities"), issued and to be issued in one or more series under an Indenture dated as of [            ] [    ], [            ] (the "Indenture"), between the Partnership and [                        ], as Trustee (the "Trustee," which term includes any successor trustee under the Indenture), to which Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights, limitations of rights, obligations, duties and immunities thereunder of the Partnership, the Trustee and the Holders of the Securities and of the terms upon which the Securities are, and are to be, authenticated and delivered. As provided in the Indenture, the Securities may be issued in one or more series, which different series may be issued in various aggregate principal amounts, may mature at different times, may bear interest, if any, at different rates, may be subject to different redemption provisions, if any, may be subject to different sinking, purchase or analogous funds, if any, may be subject to different covenants and Events of Default and may otherwise vary as in the Indenture provided or permitted. This Security is one of the series designated on the face hereof [if applicable, insert — , limited in aggregate principal amount to U.S.$            ].

        [If applicable, insert — The Securities of this series are subject to redemption upon not less than 30 nor more than 60 days' notice by mail, [if applicable, insert — (1) on                         in any year commencing with the year            and ending with the year            through operation of the sinking fund for this series at a Redemption Price equal to 100% of the principal amount, and (2)] at any time [if applicable, insert — on or after             ,            ], as a whole or in part, at the election of the Partnership, at the following Redemption Prices (expressed as percentages of the principal amount): If redeemed [if applicable, insert — on or before                        ,    %, and if redeemed] during the 12-month period beginning of the years indicated,

Year
   Redemption Price
   Year
   Redemption Price
             
             

and thereafter at a Redemption Price equal to    % of the principal amount, together in the case of any such redemption [if applicable, insert — (whether through operation of the sinking fund or otherwise)] with accrued interest to the Redemption Date, but interest installments whose Stated Maturity is on or prior to such Redemption Date will be payable to the Holders of such Securities, or one or more Predecessor Securities, of

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record at the close of business on the relevant Record Dates referred to on the face hereof, all as provided in the Indenture.]

        [If applicable, insert — The Securities of this series are subject to redemption upon not less than 30 nor more than 60 days' notice by mail, (1) on            in any year commencing with the year            and ending with the year            through operation of the sinking fund for this series at the Redemption Prices for redemption through operation of the sinking fund (expressed as percentages of the principal amount) set forth in the table below, and (2) at any time [if applicable, insert — on or after                        ], as a whole or in part, at the election of the Partnership, at the Redemption Prices for redemption otherwise than through operation of the sinking fund (expressed as percentages of the principal amount) set forth in the table below: If redeemed during the 12-month period beginning                        of the years indicated,

Year
   Redemption Price for Redemption Through Operation of the Sinking Fund
   Redemption Price for Redemption Otherwise Than Through Operation of the Sinking Fund
         
         

and thereafter at a Redemption Price equal to    % of the principal amount, together in the case of any such redemption (whether through operation of the sinking fund or otherwise) with accrued interest to the Redemption Date, but interest installments whose Stated Maturity is on or prior to such Redemption Date will be payable to the Holders of such Securities, or one or more Predecessor Securities, of record at the close of business on the relevant Record Dates referred to on the face hereof, all as provided in the Indenture.]

        [If applicable, insert — The sinking fund for this series provides for the redemption in each year beginning with the year            and ending with the year            of [if applicable, — not less than $            ("mandatory sinking fund") and not more than] $            aggregate principal amount of Securities of this series. Securities of this series acquired or redeemed by the Partnership otherwise than through [if applicable, — mandatory] sinking fund payments may be credited against subsequent [if applicable, — mandatory] sinking fund payments otherwise required to be made [if applicable, — in the inverse order in which they become due].]

        [If the Security is subject to redemption in part of any kind, insert — In the event of redemption of this Security in part only, a new Security or Securities of this series and of like tenor for the unredeemed portion hereof will be issued in the name of the Holder hereof upon the cancellation hereof.]

        [If applicable, insert — The Securities of this series are not redeemable prior to Stated Maturity.]

        [If the Security is not an Original Issue Discount Security, insert — If an Event of Default with respect to Securities of this series shall occur and be continuing, the principal of the Securities of this series may be declared due and payable in the manner and with the effect provided in the Indenture.]

        [If the Security is an Original Issue Discount Security, insert — If an Event of Default with respect to Securities of this series shall occur and be continuing, an amount of principal of the Securities of this series may be declared due and payable in the manner and with the effect provided in the Indenture. Such amount shall be equal to [insert — formula for determining the amount]. Upon payment (1) of the amount of principal so declared due and payable, and (2) of interest on any overdue principal and overdue interest (in each case to the extent that the payment of such interest shall be legally enforceable), all of the Partnership's obligations in respect of the payment of the principal of and interest, if any, on the Securities of this series shall terminate.]

        The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Partnership and the rights of the Holders of the Securities of each series to be affected under the Indenture at any time by the Partnership and the Trustee with the consent of the Holders of a majority in principal amount of the Securities at the time Outstanding of all series to be affected (voting as one class). The Indenture also contains provisions permitting the Holders of specified percentages in principal amount of the Securities of each series at the time Outstanding, on behalf of the Holders of all Securities of such series, to waive compliance by the Partnership with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by

16


the Holder of this Security shall be conclusive and binding upon such Holder and upon all future Holders of this Security and of any Security issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, regardless of whether notation of such consent or waiver is made upon this Security.

        As provided in and subject to the provisions of the Indenture, the Holder of this Security shall not have the right to institute any proceeding with respect to the Indenture or for the appointment of a receiver or trustee or for any other remedy thereunder, unless such Holder shall have previously given the Trustee written notice of a continuing Event of Default with respect to the Securities of this series, the Holders of not less than 25% in principal amount of the Securities of this series at the time Outstanding shall have made written request to the Trustee to institute proceedings in respect of such Event of Default as Trustee and offered the Trustee reasonable indemnity and the Trustee shall not have received from the Holders of a majority in principal amount of Securities of this series at the time Outstanding a direction inconsistent with such request, and shall have failed to institute any such proceeding, for 60 days after receipt of such notice, request and offer of indemnity. The foregoing shall not apply to any suit instituted by the Holder of this Security for the enforcement of any payment of principal hereof or [any premium or] interest hereon on or after the respective due dates expressed herein.

        No reference herein to the Indenture and no provision of this Security or of the Indenture shall alter or impair the obligation of the Partnership, which is absolute and unconditional, to pay the principal of and [any premium and] interest on this Security at the times, place(s) and rate, and in the coin or currency, herein prescribed.

        [If a Global Security, insert — This Global Security or portion hereof may not be exchanged for Definitive Securities of this series except in the limited circumstances provided in the Indenture.

        The holders of beneficial interests in this Global Security will not be entitled to receive physical delivery of Definitive Securities except as described in the Indenture and will not be considered the Holders thereof for any purpose under the Indenture.]

        [If a Definitive Security, insert — As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Security is registerable in the Security Register, upon surrender of this Security for registration of transfer at the office or agency of the Partnership in [if applicable, insert — any place where the principal of and any premium and interest on this Security are payable] [if applicable, insert — The City of New York [, or, subject to any laws or regulations applicable thereto and to the right of the Partnership (limited as provided in the Indenture) to rescind the designation of any such transfer agent, at the [main] offices of                                                 in                        and                         in                        or at such other offices or agencies as the Partnership may designate]], duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Partnership and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Securities of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees.]

        The Securities of this series are issuable only in registered form without coupons in denominations of U.S.$ [state other currency] and any integral multiple thereof. As provided in the Indenture and subject to certain limitations therein set forth, Securities of this series are exchangeable for a like aggregate principal amount of Securities of this series and of like tenor of a different authorized denomination, as requested by the Holder surrendering the same.

        No service charge shall be made for any such registration of transfer or exchange, but the Partnership may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

        Prior to due presentment of this Security for registration of transfer, the Partnership, the Trustee and any agent of the Partnership or the Trustee may treat the Person in whose name this Security is registered as the owner hereof for all purposes, regardless of whether this Security is overdue, and neither the Partnership, the Trustee nor any such agent shall be affected by notice to the contrary.

17


        Obligations of the Partnership under the Indenture and the Securities thereunder, including this Security, are non-recourse to TC PipeLines GP, Inc. (the "General Partner") and its Affiliates (other than the Partnership), and payable only out of cash flow and assets of the Partnership. The Trustee, and each Holder of a Security by its acceptance hereof, will be deemed to have agreed in the Indenture that (1) neither the General Partner nor its assets (nor any of its Affiliates other than the Partnership, nor their respective assets) shall be liable for any of the obligations of the Partnership under the Indenture or such Securities, including this Security, and (2) no director, officer, employee, stockholder or unitholder, as such, of the Partnership, the Trustee, the General Partner or any Affiliate of any of the foregoing entities shall have any personal liability in respect of the obligations of the Partnership under the Indenture or such Securities by reason of his, her or its status.

        The Indenture provides that the Partnership (a) will be discharged from any and all obligations in respect of the Securities (except for certain obligations described in the Indenture), or (b) need not comply with certain restrictive covenants of the Indenture, in each case if the Partnership deposits, in trust, with the Trustee money or U.S. Government Obligations (or a combination thereof) which through the payment of interest thereon and principal thereof in accordance with their terms will provide money, in an amount sufficient to pay all the principal of and interest on the Securities, but such money need not be segregated from other funds except to the extent required by law.

        This Security shall be governed by and construed in accordance with the laws of the State of New York.

        All terms used in this Security which are defined in the Indenture shall have the meanings assigned to them in the Indenture.

        [If a Definitive Security, insert as a separate page —

        FOR VALUE RECEIVED, the undersigned hereby sell(s), assign(s) and transfer(s) unto                                                 (Please Print or Typewrite Name and Address of Assignee) the within instrument of TC PIPELINES, LP and does hereby irrevocably constitute and appoint                        Attorney to transfer said instrument on the books of the within-named Partnership, with full power of substitution in the premises.

        Please Insert Social Security or Other Identifying Number of Assignee:


 
 
 
Dated:   (Signature):

Signature
 
Guarantee:

(Participant in a Recognized Signature Guaranty Medallion Program)

        NOTICE: The signature to this assignment must correspond with the name as written upon the face of the within instrument in every particular, without alteration or enlargement or any change whatever.]

SECTION 204. Global Securities.

        Every Global Security authenticated and delivered hereunder shall bear a legend in substantially the following form:

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        If Securities of a series are issuable in whole or in part in the form of one or more Global Securities, as specified as contemplated by Section 301, then, notwithstanding clause (9) of Section 301 and the provisions of Section 302, any Global Security shall represent such of the Outstanding Securities of such series as shall be specified therein and may provide that it shall represent the aggregate amount of Outstanding Securities from time to time endorsed thereon and that the aggregate amount of Outstanding Securities represented thereby may from time to time be reduced or increased, as the case may be, to reflect exchanges. Any endorsement of a Global Security to reflect the amount, or any reduction or increase in the amount, of Outstanding Securities represented thereby shall be made in such manner and upon instructions given by such Person or Persons as shall be specified therein or in a Partnership Order. Subject to the provisions of Sections 303, 304 and 305, the Trustee shall deliver and redeliver any Global Security in the manner and upon instructions given by the Person or Persons specified therein or in the applicable Partnership Order. Any instructions by the Partnership with respect to endorsement or delivery or redelivery of a Global Security shall be in a Partnership Order (which need not comply with Section 102 and need not be accompanied by an Opinion of Counsel).

        The provisions of the last sentence of Section 303 shall apply to any Security represented by a Global Security if such Security was never issued and sold by the Partnership and the Partnership delivers to the Trustee the Global Security together with a Partnership Order (which need not comply with Section 102 and need not be accompanied by an Opinion of Counsel) with regard to the reduction or increase, as the case may be, in the principal amount of Securities represented thereby, together with the written statement contemplated by the last sentence of Section 303.

SECTION 205. Form of Trustee's Certificate of Authentication.

        The Trustee's certificate of authentication shall be in substantially the following form:

        This is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.


 
 
 
As Trustee

 
 
By:
Authorized Officer

19

ARTICLE III
THE SECURITIES

SECTION 301. Amount Unlimited; Issuable in Series.

        The aggregate principal amount of Securities which may be authenticated and delivered under this Indenture is unlimited.

        The Securities may be issued in one or more series. There shall be established in or pursuant to a Board Resolution and set forth, or determined in the manner provided, in an Officers' Certificate, or established in one or more indentures supplemental hereto, prior to the issuance of Securities of any series,

20

        All Securities of any one series shall be substantially identical except as to denomination and except as may otherwise be provided in or pursuant to the Board Resolution referred to above and (subject to Section 303) set forth, or determined in the manner provided, in the Officers' Certificate referred to above or in any such indenture supplemental hereto.

        All Securities of any one series need not be issued at the same time and, unless otherwise provided, a series may be reopened, without the consent of the Holders, for increases in the aggregate principal amount of such series of Securities and issuances of additional Securities of such series or for the establishment of additional terms with respect to the Securities of such series.

21


        If any of the terms of the series are established by action taken by or pursuant to a Board Resolution, a copy of an appropriate record of such action shall be certified by an authorized officer or other authorized person of the General Partner on behalf of the Partnership and delivered to the Trustee at or prior to the delivery of the Officers' Certificate setting forth, or providing the manner for determining, the terms of the series.

        With respect to Securities of a series subject to a Periodic Offering, such Board Resolution or Officers' Certificate may provide general terms for Securities of such series and provide either that the specific terms of particular Securities of such series shall be specified in a Partnership Order, or that such terms shall be determined by the Partnership, or one or more of the Partnership's agents designated in an Officers' Certificate, in accordance with a Partnership Order. Unless otherwise specifically provided with respect to a particular series of Securities, at any time the Partnership may purchase Securities in the open market, by tender or by contract.

SECTION 302. Denominations.

        The Securities of each series shall be issuable only in registered form without coupons in such denominations as shall be specified as contemplated by Section 301. In the absence of any such specified denomination with respect to the Securities of any series, the Securities of such series shall be issuable in denominations of $1,000 and any integral multiple thereof.

SECTION 303. Execution, Authentication, Delivery and Dating.

        The Securities shall be executed on behalf of the Partnership by the Chief Executive Officer, Chief Financial Officer, President or any Vice President of the General Partner and need not be attested. The signature of any of these officers on the Securities may be manual or facsimile.

        Securities bearing the manual or facsimile signatures of individuals who were at any time the proper officers of the General Partner shall bind the Partnership, notwithstanding that such individuals or any of them have ceased to hold such offices prior to the authentication and delivery of such Securities or did not hold such offices at the date of such Securities.

        At any time and from time to time after the execution and delivery of this Indenture, the Partnership may deliver Securities of any series executed by the Partnership to the Trustee for authentication, together with a Partnership Order for the authentication and delivery of such Securities, and the Trustee in accordance with the Partnership Order shall authenticate and deliver such Securities; provided, however, that in the case of Securities offered in a Periodic Offering, the Trustee shall authenticate and deliver such Securities from time to time in accordance with such other procedures (including, without limitation, the receipt by the Trustee of oral or electronic instructions from the Partnership or its duly authorized agents, thereafter promptly confirmed in writing) acceptable to the Trustee as may be specified by or pursuant to a Partnership Order delivered to the Trustee prior to the time of the first authentication of Securities of such series. If the form or terms of the Securities of the series have been established in or pursuant to one or more Board Resolutions as permitted by Sections 201 and 301, in authenticating such Securities, and accepting the additional responsibilities under this Indenture in relation to such Securities, the Trustee shall be entitled to receive such documents as it may reasonably request. The Trustee shall also be entitled to receive, and (subject to Section 601) shall be fully protected in relying upon, an Opinion of Counsel stating,

22

        If such form or forms or terms have been so established, the Trustee shall not be required to authenticate such Securities if the issue of such Securities pursuant to this Indenture will affect the Trustee's own rights, duties or immunities under the Securities and this Indenture or otherwise in a manner which is not reasonably acceptable to the Trustee.

        Notwithstanding the provisions of Section 301 and of the preceding paragraph, if all Securities of a series are not to be originally issued at one time, it shall not be necessary to deliver the Officers' Certificate otherwise required pursuant to Section 301 or the Partnership Order and Opinion of Counsel otherwise required pursuant to such preceding paragraph at or prior to the time of authentication of each Security of such series if such documents are delivered at or prior to the authentication upon original issuance of the first Security of such series to be issued.

        With respect to Securities of a series offered in a Periodic Offering, the Trustee may rely, as to the authorization by the Partnership of any of such Securities, the form or forms and terms thereof and the legality, validity, binding effect and enforceability thereof, upon the Opinion of Counsel and the other documents delivered pursuant to Sections 201 and 301 and this Section 303, as applicable, in connection with the first authentication of Securities of such series.

        Each Security shall be dated the date of its authentication.

        No Security shall be entitled to any benefit under this Indenture or be valid or obligatory for any purpose unless there appears on such Security a certificate of authentication substantially in the form provided for herein executed by the Trustee by manual signature of an authorized officer, and such certificate upon any Security shall be conclusive evidence, and the only evidence, that such Security has been duly authenticated and delivered hereunder and is entitled to the benefits of this Indenture.

        Notwithstanding the foregoing, if any Security shall have been authenticated and delivered hereunder but never issued and sold by the Partnership, and the Partnership shall deliver such Security to the Trustee for cancellation as provided in Section 309 for all purposes of this Indenture, such Security shall be deemed never to have been authenticated and delivered hereunder and shall never be entitled to the benefits of this Indenture.

SECTION 304. Temporary Securities.

        Pending the preparation of Definitive Securities of any series, the Partnership may execute, and upon Partnership Order the Trustee shall authenticate and deliver, temporary Securities which are printed, lithographed, typewritten, mimeographed or otherwise produced, in any authorized denomination, substantially of the tenor of the Definitive Securities in lieu of which they are issued and with such appropriate insertions, omissions, substitutions and other variations as the officers executing such Securities may determine, as evidenced by their execution of such Securities.

        If temporary Securities of any series are issued, the Partnership will cause Definitive Securities of that series to be prepared without unreasonable delay. After the preparation of Definitive Securities of such series, the temporary Securities of such series shall be exchangeable for Definitive Securities of such series upon surrender of the temporary Securities of such series at the office or agency of the Partnership maintained pursuant to Section 1002 for the purpose of exchanges of Securities of such series, without charge to the Holder. Upon

23


surrender for cancellation of any one or more temporary Securities of any series the Partnership shall execute and the Trustee shall authenticate and deliver in exchange therefor Definitive Securities of the same series and tenor, of any authorized denominations and of a like aggregate principal amount. Until so exchanged the temporary Securities of any series shall in all respects be entitled to the same benefits under this Indenture as Definitive Securities of such series and tenor.

SECTION 305. Registration, Registration of Transfer and Exchange.

        The Partnership shall cause to be kept at the office or agency of the Partnership in the [                        ] (or in any other office or agency of the Partnership in a Place of Payment required by Section 1002) a register (the register maintained in such office being herein sometimes referred to as the "Security Register") in which, subject to such reasonable regulations as it may prescribe, the Partnership shall provide for the registration of Securities and of transfers of Securities. The Trustee is hereby appointed as the initial "Security Registrar" for the purpose of registering Securities and transfers of Securities as herein provided and its corporate trust office which, at the date hereof, is located at [                        ], as the initial office or agency in [                        ] where the Security Register will be maintained. The Partnership may at any time replace such Security Registrar, change such office or agency or act as its own Security Registrar. The Partnership will give prompt written notice to the Trustee of any change of the Security Registrar or of the location of such office or agency.

        Upon surrender for registration of transfer of any Security of any series at the office or agency of the Partnership maintained pursuant to Section 1002 for such purpose, the Partnership shall execute, and the Trustee shall authenticate and deliver, in the name of the designated transferee or transferees, one or more new Securities of the same series and tenor, of any authorized denominations and of a like aggregate principal amount.

        At the option of the Holder, Securities of any series (except a Global Security) may be exchanged for other Securities of the same series and tenor, of any authorized denominations and of a like aggregate principal amount, upon surrender of the Securities to be exchanged at such office or agency. Whenever any Securities are so surrendered for exchange, the Partnership shall execute, and the Trustee shall authenticate and deliver, the Securities which the Holder making the exchange is entitled to receive.

        All Securities issued upon any registration of transfer or exchange of Securities shall be the valid obligations of the Partnership, evidencing the same debt, and entitled to the same benefits under this Indenture, as the Securities surrendered upon such registration of transfer or exchange.

        Every Security presented or surrendered for registration of transfer or for exchange shall (if so required by the Partnership or the Trustee) be duly endorsed, or be accompanied by a written instrument of transfer in form satisfactory to the Partnership and the Security Registrar duly executed, by the Holder thereof or his attorney duly authorized in writing.

        No service charge shall be imposed for any registration of transfer or exchange of Securities, but the Partnership may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in connection with any registration of transfer or exchange of Securities, other than exchanges pursuant to Section 304, 906 or 1107 not involving any transfer.

        Neither the Trustee nor the Partnership shall be required (1) to issue, register the transfer of or exchange Securities of any series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of Securities of that series selected for redemption under Section 1103 and ending at the close of business on the day of such mailing, or (2) to register the transfer of or exchange any Security so selected for redemption in whole or in part, except the unredeemed portion of any Security being redeemed in part.

        Notwithstanding any other provisions of this Indenture and except as otherwise specified with respect to any particular series of Securities as contemplated by Section 301, a Global Security representing all or a portion of the Securities of a series may not be transferred, except as a whole by the Depositary for such series to a nominee of such Depositary or by a nominee of such Depositary to such Depositary or another nominee of such Depositary or by such Depositary or any such nominee to a successor Depositary for such series or a nominee of such successor Depositary. Every Security authenticated and delivered upon registration or transfer of or in

24


exchange for or in lieu of, a Global Security shall be a Global Security except as provided in the two paragraphs immediately following.

        If at any time the Depositary for any Securities of a series represented by one or more Global Securities notifies the Partnership that it is unwilling or unable to continue as Depositary for such Securities or if at any time the Depositary for such Securities shall no longer be eligible to continue as Depositary under Section 101 or ceases to be a clearing agency registered under the Exchange Act, the Partnership shall appoint a successor Depositary with respect to such Securities. If a successor Depositary for such Securities is not appointed by the Partnership within 90 days after the Partnership receives such notice or becomes aware of such ineligibility, the Partnership's election pursuant to Section 301 that such Securities be represented by one or more Global Securities shall no longer be effective and the Partnership will execute, and the Trustee, upon receipt of a Partnership Order for the authentication and delivery of Definitive Securities of such series, will authenticate and deliver, Securities of such series in definitive registered form without coupons, in any authorized denominations, in an aggregate principal amount equal to the principal amount of the Global Security or Securities representing such Securities in exchange for such Global Security or Securities registered in the names of such Persons as the Depository shall direct.

        The Partnership may at any time and in its sole discretion determine that the Securities of any series issued in the form of one or more Global Securities shall no longer be represented by a Global Security or Securities. In such event the Partnership will execute, and the Trustee, upon receipt of a Partnership Order for the authentication and delivery of the Definitive Securities of such series, will authenticate and deliver, Securities of such series in definitive registered form without coupons, in any authorized denominations, in an aggregate principal amount equal to the principal amount of the Global Security or Securities representing such Securities in exchange for such Global Security or Securities registered in the names of such Persons as the Depository shall direct.

        If specified by the Partnership pursuant to Section 301 with respect to Securities represented by a Global Security, the Depositary for such Global Security may surrender such Global Security in exchange in whole or in part for Securities of the same series and tenor in definitive registered form on such terms as are acceptable to the Partnership and such Depositary. Thereupon, the Partnership shall execute, and the Trustee, upon receipt of a Partnership Order for the authentication and delivery of Securities in definitive registered form, shall authenticate and deliver, without service charge,

        Every Person who takes or holds any beneficial interest in a Global Security agrees that:

25

SECTION 306. Mutilated, Destroyed, Lost and Stolen Securities.

        If any mutilated Security is surrendered to the Trustee, together with such security or indemnity as may be required by the Partnership or the Trustee to save each of them and any agent of either of them harmless, the Partnership shall execute and the Trustee shall authenticate and deliver in exchange therefor a new Security of the same series and of like tenor and principal amount and bearing a number not contemporaneously Outstanding.

        If there shall be delivered to the Partnership and the Trustee (1) evidence to their satisfaction of the destruction, loss or theft of any Security and (2) such security or indemnity as may be required by them to save each of them and any agent of either of them harmless, then, in the absence of notice to the Partnership or the Trustee that such Security has been acquired by a bona fide purchaser, the Partnership shall execute and the Trustee shall authenticate and deliver, in lieu of any such destroyed, lost or stolen Security, a new Security of the same series and of like tenor and principal amount and bearing a number not contemporaneously Outstanding.

        In case any such mutilated, destroyed, lost or stolen Security has become or is about to become due and payable, the Partnership in its discretion may, instead of issuing a new Security, pay such Security.

        Upon the issuance of any new Security under this Section 306, the Partnership may require the payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in relation thereto and any other expenses (including the fees and expenses of the Trustee) connected therewith. Every new Security of any series issued pursuant to this Section 306 in lieu of any destroyed, lost or stolen Security shall constitute an original additional contractual obligation of the Partnership, whether or not the mutilated, destroyed, lost or stolen Security shall be at any time enforceable by anyone, and shall be entitled to all the benefits of this Indenture equally and proportionately with any and all other Securities of that series duly issued hereunder.

        The provisions of this Section 306 are exclusive and shall preclude (to the extent lawful) all other rights and remedies with respect to the replacement or payment of mutilated, destroyed, lost or stolen Securities.

SECTION 307. Payment of Interest; Interest Rights Preserved.

        Except as otherwise provided as contemplated by Section 301 with respect to any series of Securities, interest on any Security which is payable, and is punctually paid or duly provided for, on any Interest Payment Date shall be paid to the Person in whose name that Security (or one or more Predecessor Securities) is registered at the close of business on the Regular Record Date for such interest.

        Any interest on any Security of any series which is payable, but is not punctually paid or duly provided for, on any Interest Payment Date (herein called "Defaulted Interest") shall forthwith cease to be payable to the Holder on the relevant Regular Record Date by virtue of having been such Holder, and such Defaulted Interest may be paid by the Partnership, at its election in each case, as provided in clause (1) or (2) below:

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        Subject to the foregoing provisions of this Section 307 and Section 305, each Security delivered under this Indenture upon registration of transfer of or in exchange for or in lieu of any other Security, shall carry the rights to interest accrued and unpaid, and to accrue, which were carried by such other Security.

SECTION 308. Persons Deemed Owners.

        Except as otherwise provided as contemplated by Section 301 with respect to any series of Securities, prior to due presentment of a Security for registration of transfer, the Partnership, the Trustee and any agent of the Partnership or the Trustee may treat the Person in whose name such Security is registered as the owner of such Security for the purpose of receiving payment of principal of and any premium and (subject to Sections 305 and 307) any interest on such Security and for all other purposes whatsoever, whether or not such Security is overdue, and neither the Partnership, the Trustee nor any agent of the Partnership or the Trustee shall be affected by notice to the contrary.

        No holder of any beneficial interest in any Global Security held on its behalf by a Depositary shall have any rights under this Indenture with respect to such Global Security, and such Depositary may be treated by the Partnership, the Trustee and any agent of the Partnership or the Trustee as the owner of such Global Security for all purposes whatsoever. None of the Partnership, the Trustee nor any agent of the Partnership or the Trustee will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests of a Global Security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

SECTION 309. Cancellation.

        All Securities surrendered for payment, redemption, registration of transfer or exchange or for credit against any sinking fund payment shall, if surrendered to any Person other than the Trustee, be delivered to the Trustee and shall be promptly canceled by it. The Partnership may at any time deliver to the Trustee for cancellation any Securities previously authenticated and delivered hereunder which the Partnership may have acquired in any manner whatsoever, and may deliver to the Trustee (or to any other Person for delivery to the Trustee) for cancellation any Securities previously authenticated hereunder which the Partnership has not issued and sold, and all Securities so delivered shall be promptly canceled by the Trustee. No Securities shall be authenticated in lieu of or in exchange for any Securities canceled as provided in this Section 309, except as expressly permitted by this Indenture. All canceled Securities held by the Trustee shall be disposed of in accordance with its customary practices, and the Trustee shall thereafter deliver to the Partnership a certificate with respect to such disposition.

SECTION 310. Computation of Interest.

        Except as otherwise specified as contemplated by Section 301 for Securities of any series, interest on the Securities of each series shall be computed on the basis of a 360-day year of twelve 30-day months and interest on the Securities of each series for any partial period shall be computed on the basis of a 360-day year of twelve 30-day months and the number of days elapsed in any partial month.

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SECTION 311. CUSIP Numbers.

        The Partnership in issuing the Securities may use "CUSIP" numbers (if then generally in use, and in addition to the other identification numbers printed on the Securities), and, if so, the Trustee shall use "CUSIP" numbers in notices of redemption as a convenience to Holders; provided, however, that any such notice may state that no representation is made as to the correctness of such "CUSIP" numbers either as printed on the Securities or as contained in any notice of a redemption and that reliance may be placed only on the other identification numbers printed on the Securities, and any such redemption shall not be affected by any defect in or omission of such "CUSIP" numbers.

ARTICLE IV
SATISFACTION AND DISCHARGE

SECTION 401. Satisfaction and Discharge of Indenture.

        This Indenture shall upon Partnership Request cease to be of further effect with respect to Securities of any series (except as to any surviving rights of registration of transfer or exchange of such Securities herein expressly provided for), and the Trustee, at the expense of the Partnership, shall execute proper instruments acknowledging satisfaction and discharge of this Indenture with respect to such Securities, when

and the Partnership in the case of (i), (ii) or (iii) above, has irrevocably deposited or caused to be deposited with the Trustee as trust funds in trust for this purpose an amount of money in the currency or currency units in which such Securities are payable sufficient to pay and discharge the entire indebtedness on such Securities not theretofore delivered to the Trustee for cancellation, for principal and any premium and interest to the date of such deposit (in the case of Securities which have become due and payable) or to the Stated Maturity or Redemption Date, as the case may be;

        Notwithstanding the satisfaction and discharge of this Indenture with respect to Securities of any series, (x) the obligations of the Partnership to the Trustee under Section 607, the obligations of the Trustee to any Authenticating Agent under Section 614 and the right of the Trustee to resign under Section 610 shall survive, and (y) if money shall have been deposited with the Trustee pursuant to subclause (b) of clause (1) of this Section 401, the obligations of the Partnership and/or the Trustee under Sections 402, 606, 701 and 1002 and the last paragraph of Section 1003 shall survive.

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SECTION 402. Application of Trust Money.

        Subject to the provisions of the last paragraph of Section 1003, all money deposited with the Trustee pursuant to Section 401 shall be held in trust and applied by it, in accordance with the provisions of the Securities and this Indenture, to the payment, either directly or through any Paying Agent (including the Partnership acting as its own Paying Agent) as the Trustee may determine, to the Persons entitled thereto, of the principal and any premium and interest for whose payment such money has been deposited with the Trustee.

ARTICLE V
REMEDIES

SECTION 501. Events of Default.

        "Event of Default," wherever used herein with respect to Securities of any series, means any one of the following events (whatever the reason for such Event of Default and whether it shall be voluntary or involuntary or be effected by operation of law or pursuant to any judgment, decree or order of any court or any order, rule or regulation of any administrative or governmental body):

SECTION 502. Acceleration of Maturity; Rescission and Annulment.

        If an Event of Default with respect to Securities of any series at the time Outstanding occurs and is continuing, then in every such case the Trustee or the Holders of not less than 25% in principal amount of the Outstanding Securities of that series may declare the principal amount of (or, if any of the Securities of that series are Original Issue Discount Securities, such portion of the principal amount of such Securities as may be specified in the terms thereof), and accrued but unpaid interest, if any, on all of the Securities of that series to be due and payable immediately, by a notice in writing to the Partnership (and to the Trustee if given by Holders), and upon any such declaration such principal amount (or specified amount) shall become immediately due and payable. Notwithstanding the foregoing, if an Event of Default specified in clause (4) or (5) of Section 501 occurs, the Securities of any series at the time Outstanding shall be due and payable immediately without further action or notice.

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        At any time after such a declaration of acceleration with respect to Securities of any series has been made and before a judgment or decree for payment of the money due has been obtained by the Trustee as hereinafter in this Article provided, the Holders of a majority in principal amount of the Outstanding Securities of that series, by written notice to the Partnership and the Trustee, may rescind and annul such declaration and its consequences if:

        No such rescission shall affect any subsequent Default or impair any right consequent thereon.

SECTION 503. Collection of Indebtedness and Suits for Enforcement by Trustee.

        The Partnership covenants that if

the Partnership will, upon demand of the Trustee, pay to it, for the benefit of the Holders of such Securities, the whole amount then due and payable on such Securities for principal and any premium and interest and, to the extent that payment of such interest shall be legally enforceable, interest on any overdue principal and premium and on any overdue interest, at the rate or rates prescribed therefor in such Securities, and, in addition thereto, such further amount as shall be sufficient to cover the costs and expenses of collection, including the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel.

        If the Partnership fails to pay such amounts forthwith upon such demand, the Trustee, in its own name and as trustee of an express trust, may institute a judicial proceeding for the collection of the sums so due and unpaid, may prosecute such proceeding to judgment or final decree and may enforce the same against the Partnership or any other obligor upon such Securities and collect the moneys adjudged or decreed to be payable in the manner provided by law out of the property of the Partnership or any other obligor upon such Securities, wherever situated.

        If an Event of Default with respect to Securities of any series occurs and is continuing, the Trustee may in its discretion proceed to protect and enforce its rights and the rights of the Holders of Securities of such series by such appropriate judicial proceedings as the Trustee shall deem most effectual to protect and enforce any such rights, whether for the specific enforcement of any covenant or agreement in this Indenture or in aid of the exercise of any power granted herein, or to enforce any other proper remedy.

SECTION 504. Trustee May File Proofs of Claim.

        In case of the pendency of any receivership, insolvency, liquidation, bankruptcy, reorganization, arrangement, adjustment, composition or other judicial proceeding relative to the Partnership or any other obligor upon the Securities, their property or their creditors, the Trustee (irrespective of whether the principal of

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the Securities shall then be due and payable as therein expressed or by declaration or otherwise and irrespective of whether the Trustee shall have made any demand on the Partnership for the payment of overdue principal or interest) shall be entitled and empowered, by intervention in such proceeding or otherwise,

and any custodian, receiver, assignee, trustee, liquidator, sequestrator or other similar official in any such judicial proceeding is hereby authorized by each Holder to make such payments to the Trustee and, in the event that the Trustee shall consent to the making of such payments directly to the Holders, to pay to the Trustee any amount due it for the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel, and any other amounts due the Trustee under Section 607.

        No provision of this Indenture shall be deemed to authorize the Trustee to authorize or consent to or accept or adopt on behalf of any Holder any plan of reorganization, arrangement, adjustment or composition affecting the Securities or the rights of any Holder thereof or to authorize the Trustee to vote in respect of the claim of any Holder in any such proceeding; provided, however, that the Trustee may, on behalf of the Holders, vote for the election of a trustee in bankruptcy or similar official and be a member of a creditors' or other similar committee.

SECTION 505. Trustee May Enforce Claims Without Possession of Securities.

        All rights of action and claims under this Indenture or the Securities may be prosecuted and enforced by the Trustee without the possession of any of the Securities or the production thereof in any proceeding relating thereto, and any such proceeding instituted by the Trustee shall be brought in its own name as trustee of an express trust, and any recovery of judgment shall, after provision for the payment of the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel, be for the ratable benefit of the Holders of the Securities in respect of which such judgment has been recovered.

SECTION 506. Application of Money Collected.

        Any money collected by the Trustee pursuant to this Article shall be applied in the following order, at the date or dates fixed by the Trustee and, in case of the distribution of such money on account of principal or any premium or interest, upon presentation of the Securities and the notation thereon of the payment if only partially paid and upon surrender thereof if fully paid:

    FIRST:   To the payment of all amounts due the Trustee under Section 607;

 
 
SECOND:
 
To the payment of the amounts then due and unpaid for principal of and any premium and interest on the Securities in respect of which or for the benefit of which such money has been collected, ratably, without preference or priority of any kind, according to the amounts due and payable on such Securities for principal and any premium and interest, respectively; and

 
 
THIRD:
 
The balance, if any, to the Partnership.

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SECTION 507. Limitation on Suits.

        No Holder of any Security of any series shall have any right to institute any proceeding, judicial or otherwise, with respect to this Indenture, or for the appointment of a receiver or trustee, or for any other remedy hereunder, unless:

it being understood and intended that no one or more of such Holders shall have any right in any manner whatever by virtue of, or by availing of, any provision of this Indenture to affect, disturb or prejudice the rights of any other of such Holders, or to obtain or to seek to obtain priority or preference over any other of such Holders or to enforce any right under this Indenture, except in the manner herein provided and for the equal and ratable benefit of all such Holders.

SECTION 508. Unconditional Right of Holders to Receive Principal, Premium and Interest.

        Notwithstanding any other provision in this Indenture, the Holder of any Security shall have the right, which is absolute and unconditional, to receive payment of the principal of and any premium and (subject to Sections 305 and 307) interest on such Security on the respective Stated Maturity or Maturities expressed in such Security (or, in the case of redemption, on the Redemption Date) and to institute suit for the enforcement of any such payment, and such rights shall not be impaired without the consent of such Holder.

SECTION 509. Restoration of Rights and Remedies.

        If the Trustee or any Holder has instituted any proceeding to enforce any right or remedy under this Indenture and such proceeding has been discontinued or abandoned for any reason, or has been determined adversely to the Trustee or to such Holder, then and in every such case, subject to any determination in such proceeding, the Partnership, the Trustee and the Holders shall be restored severally and respectively to their former positions hereunder, and thereafter all rights and remedies of the Trustee and the Holders shall continue as though no such proceeding had been instituted.

SECTION 510. Rights and Remedies Cumulative.

        Except as otherwise provided with respect to the replacement or payment of mutilated, destroyed, lost or stolen Securities in the last paragraph of Section 306, no right or remedy herein conferred upon or reserved to the Trustee or to the Holders is intended to be exclusive of any other right or remedy, and every right and remedy shall, to the extent permitted by law, be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in equity or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent the concurrent assertion or employment of any other appropriate right or remedy.

SECTION 511. Delay or Omission Not Waiver.

        No delay or omission of the Trustee or of any Holder of any Securities to exercise any right or remedy accruing upon any Event of Default shall impair any such right or remedy or constitute a waiver of any such

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Event of Default or an acquiescence therein. Every right and remedy given by this Article or by law to the Trustee or to the Holders may be exercised from time to time, and as often as may be deemed expedient, by the Trustee or by the Holders, as the case may be.

SECTION 512. Control by Holders.

        The Holders of a majority in aggregate principal amount of the Outstanding Securities of any series shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred on the Trustee, with respect to the Securities of such series; provided, however, that:

SECTION 513. Waiver of Past Defaults.

        The Holders of not less than a majority in principal amount of the Outstanding Securities of any series may on behalf of the Holders of all the Securities of such series waive any past default hereunder with respect to such series and its consequences, except:

        Upon any such waiver, such default shall cease to exist, and any Event of Default arising therefrom shall be deemed to have been cured, for every purpose of this Indenture, but no such waiver shall extend to any subsequent or other default or impair any right consequent thereon.

SECTION 514. Undertaking for Costs.

        All parties to this Indenture agree, and each Holder of any Security by his acceptance thereof shall be deemed to have agreed, that any court may in its discretion require, in any suit for the enforcement of any right or remedy under this Indenture, or in any suit against the Trustee for any action taken, suffered or omitted by it as Trustee, the filing by any party litigant, other than the Trustee, in such suit of an undertaking to pay the costs of such suit, and that such court may in its discretion assess reasonable costs, including reasonable attorneys' fees, against any party litigant in such suit, having due regard to the merits and good faith of the claims or defenses made by such party litigant; but the provisions of this Section 514 shall not apply to any suit instituted by the Partnership, to any suit instituted by the Trustee, to any suit instituted by any Holder, or group of Holders, holding in the aggregate more than 10% in principal amount of the Outstanding Securities of any series, or to any suit instituted by any Holder for the enforcement of the payment of the principal of, or premium, if any, or interest on any Security on or after the Stated Maturity or Maturities expressed in such Security (or, in the case of redemption, on or after the Redemption Date).

SECTION 515. Waiver of Usury, Stay or Extension Laws.

        The Partnership covenants (to the extent that it may lawfully do so) that it will not at any time insist upon, or plead, or in any manner whatsoever claim or take the benefit or advantage of, any usury, stay or extension law wherever enacted, now or at any time hereafter in force, which may affect the covenants or the performance of this Indenture; and the Partnership (to the extent that it may lawfully do so) hereby expressly waives all benefit or advantage of any such law and covenants that it will not hinder, delay or impede the execution of any power

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herein granted to the Trustee, but will suffer and permit the execution of every such power as though no such law had been enacted.

ARTICLE VI
THE TRUSTEE

SECTION 601. Certain Duties and Responsibilities.

        (a)   If an Event of Default has occurred and is continuing, the Trustee shall exercise the rights and powers vested in it by this Indenture and use the same degree of care and skill in its exercise as a prudent Person would exercise or use under the circumstances in the conduct of such Person's own affairs.

        (b)   Except during the continuance of an Event of Default,

        (c)   In case an Event of Default has occurred and is continuing, the Trustee shall exercise such of the rights and powers vested in it by this Indenture, and use the same degree of care and skill in their exercise, as a prudent man would exercise or use under the circumstances in the conduct of his own affairs.

        (d)   No provision of this Indenture shall be construed to relieve the Trustee from liability for its own negligent action, its own negligent failure to act, or its own willful misconduct, except that

        (e)   Whether or not therein expressly so provided, every provision of this Indenture relating to the conduct or affecting the liability of or affording protection to the Trustee shall be subject to the provisions of this Section 601.

SECTION 602. Notice of Defaults.

        Within 90 days after the occurrence of any default hereunder with respect to the Securities of any series, the Trustee shall transmit by mail to all Holders of Securities of such series, as their names and addresses appear in the Security Register, notice of such default hereunder known to the Trustee, unless such Default shall have been cured or waived; provided, however, that, except in the case of a Default in the payment of the principal of or any premium or interest on any Security of such series or in the payment of any sinking fund installment with

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respect to Securities of such series, the Trustee shall be protected in withholding such notice if and so long as the board of directors, the executive committee or a trust committee of directors and/or Responsible Officers of the Trustee in good faith determine that the withholding of such notice is in the interest of the Holders of Securities of such series; and, provided, further, that in the case of any Default of the character specified in Section 501(3) with respect to Securities of such series, no such notice to Holders shall be given until at least 90 days after the occurrence thereof.

SECTION 603. Certain Rights of Trustee.

        Subject to the provisions of Section 601:

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SECTION 604. Not Responsible for Recitals or Issuance of Securities.

        The recitals contained herein and in the Securities, except the Trustee's certificates of authentication, shall be taken as the statements of the Partnership, and the Trustee or any Authenticating Agent assumes no responsibility for their correctness. Neither the Trustee nor any Authenticating Agent makes any representations as to the validity or sufficiency of this Indenture or of the Securities. Neither the Trustee nor any Authenticating Agent shall be accountable for the use or application by the Partnership of Securities or the proceeds thereof.

SECTION 605. May Hold Securities.

        The Trustee, any Authenticating Agent, any Paying Agent, any Security Registrar or any other agent of the Partnership, in its individual or any other capacity, may become the owner or pledgee of Securities and, subject to Sections 310(b) and 311 of the Trust Indenture Act and Sections 608, 609 and 613 hereof, may otherwise deal with the Partnership with the same rights it would have if it were not Trustee, Authenticating Agent, Paying Agent, Security Registrar or such other agent.

SECTION 606. Money Held in Trust.

        Money held by the Trustee in trust hereunder need not be segregated from other funds except to the extent required by law. The Trustee shall be under no liability for interest on any money received by it hereunder except as otherwise agreed in writing with the Partnership.

SECTION 607. Compensation and Reimbursement.

        The Partnership agrees

        As security for the performance of the obligations of the Partnership under this Section 607 the Trustee shall have a lien prior to the Securities upon all property and funds held or collected by the Trustee as such, except funds held in trust for the payment of principal of (and premium, if any) or interest on particular Securities.

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        Without limiting any rights available to the Trustee under applicable law, when the Trustee incurs expenses or renders services in connection with an Event of Default specified in Section 501(4) or Section 501(5), the expenses (including the reasonable charges and expenses of its counsel) and the compensation for the services of the Trustee are intended to constitute expenses of administration under any applicable Bankruptcy Law.

        The provisions of this Section 607 shall survive the satisfaction and discharge of this Indenture and the defeasance of the Securities.

SECTION 608. Disqualification; Conflicting Interests.

        Reference is made to Section 310(b) of the Trust Indenture Act. There shall be excluded from the operation of Section 310(b)(1) of the Trust Indenture Act this Indenture with respect to the Securities of more than one series.

SECTION 609. Corporate Trustee Required; Eligibility.

        There shall at all times be a Trustee hereunder which shall be a corporation organized and doing business under the laws of the United States of America, any State thereof or the District of Columbia, authorized under such laws to exercise corporate trust powers, having a combined capital and surplus required by the Trust Indenture Act, subject to supervision or examination by Federal or State authority. If such corporation publishes reports of condition at least annually, pursuant to law or to the requirements of said supervising or examining authority, then for the purposes of this Section 609, the combined capital and surplus of such corporation shall be deemed to be its combined capital and surplus as set forth in its most recent report of condition so published. The Trustee shall not be an obligor upon the Securities or an Affiliate thereof. If at any time the Trustee shall cease to be eligible in accordance with the provisions of this Section 609, it shall resign immediately in the manner and with the effect hereinafter specified in this Article.

SECTION 610. Resignation and Removal; Appointment of Successor.

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SECTION 611. Acceptance of Appointment by Successor.

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SECTION 612. Merger, Conversion, Consolidation or Succession to Business.

        Any corporation into which the Trustee may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, conversion or consolidation to which the Trustee shall be a party, or any corporation succeeding to all or substantially all the corporate trust business of the Trustee, shall be the successor of the Trustee hereunder, provided such corporation shall be otherwise qualified and eligible under this Article, without the execution or filing of any paper or any further act on the part of any of the parties hereto. In case any Securities shall have been authenticated, but not delivered, by the Trustee then in office, any successor by merger, conversion or consolidation to such authenticating Trustee may adopt such authentication and deliver the Securities so authenticated with the same effect as if such successor Trustee had itself authenticated such Securities.

SECTION 613. Preferential Collection of Claims Against Partnership.

        Reference is made to Section 311 of the Trust Indenture Act. For purposes of Section 311(b) of the Trust Indenture Act,

SECTION 614. Appointment of Authenticating Agent.

        The Trustee may appoint an Authenticating Agent or Agents with respect to one or more series of Securities which shall be authorized to act on behalf of the Trustee to authenticate Securities of such series issued upon exchange, registration of transfer or partial redemption thereof or pursuant to Section 306, and Securities so authenticated shall be entitled to the benefits of this Indenture and shall be valid and obligatory for all purposes as if authenticated by the Trustee hereunder. Wherever reference is made in this Indenture to the authentication and delivery of Securities by the Trustee or the Trustee's certificate of authentication, such reference shall be deemed to include authentication and delivery on behalf of the Trustee by an Authenticating Agent and a certificate of authentication executed on behalf of the Trustee by an Authenticating Agent. Each Authenticating Agent shall be acceptable to the Partnership and shall at all times be

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a corporation organized and doing business under the laws of the United States of America, any State thereof or the District of Columbia, authorized under such laws to act as Authenticating Agent, having a combined capital and surplus of not less than $50,000,000 and subject to supervision or examination by Federal or State authority. If such Authenticating Agent publishes reports of condition at least annually, pursuant to law or to the requirements of said supervising or examining authority, then for the purposes of this Section 614, the combined capital and surplus of such Authenticating Agent shall be deemed to be its combined capital and surplus as set forth in its most recent report of condition so published. If at any time an Authenticating Agent shall cease to be eligible in accordance with the provisions of this Section 614, such Authenticating Agent shall resign immediately in the manner and with the effect specified in this Section 614.

        Any corporation into which an Authenticating Agent may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, conversion or consolidation to which such Authenticating Agent shall be a party, or any corporation succeeding to all or substantially all of the corporate agency or corporate trust business of an Authenticating Agent, shall continue to be an Authenticating Agent, provided such corporation shall be otherwise eligible under this Section 614, without the execution or filing of any paper or any further act on the part of the Trustee or the Authenticating Agent.

        An Authenticating Agent may resign at any time by giving written notice thereof to the Trustee and to the Partnership. The Trustee may at any time terminate the agency of an Authenticating Agent by giving written notice thereof to such Authenticating Agent and to the Partnership. Upon receiving such a notice of resignation or upon such a termination, or in case at any time such Authenticating Agent shall cease to be eligible in accordance with the provisions of this Section 614, the Trustee may appoint a successor Authenticating Agent which shall be acceptable to the Partnership and shall mail written notice of such appointment by first class mail, postage prepaid, to all Holders of Securities of the series with respect to which such Authenticating Agent will serve, as their names and addresses appear in the Security Register. Any successor Authenticating Agent upon acceptance of its appointment hereunder shall become vested with all the rights, powers and duties of its predecessor hereunder, with like effect as if originally named as an Authenticating Agent. No successor Authenticating Agent shall be appointed unless eligible under the provisions of this Section 614.

        Except with respect to an Authenticating Agent appointed at the request of the Partnership, the Trustee agrees to pay to each Authenticating Agent from time to time reasonable compensation for its services under this Section 614, and the Trustee shall be entitled to be reimbursed by the Partnership for such payments, subject to the provisions of Section 607.

        If an appointment with respect to one or more series is made pursuant to this Section 614, the Securities of such series may have endorsed thereon, in addition to the Trustee's certificate of authentication, an alternate certificate of authentication in the following form:

        This is one of the Securities of the series designated therein referred to in the within mentioned Indenture.

   
As Trustee

 
 
By:
 
As Authorized Agent

 
 
By:
 
Authorized Officer

ARTICLE VII
HOLDERS' LISTS AND REPORTS BY TRUSTEE AND PARTNERSHIP

SECTION 701. Partnership to Furnish Trustee Names and Addresses of Holders.

        The Partnership will furnish or cause to be furnished to the Trustee

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provided, however, that if and so long as the Trustee shall be the Security Registrar, no such list need be furnished with respect to such series of Securities.

SECTION 702. Preservation of Information; Communications to Holders.

        If the Trustee shall elect not to afford such applicants access to such information, the Trustee shall, upon the written request of such applicants, mail to each Holder whose name and address appear in the information preserved at the time by the Trustee in accordance with Section 702(a) a copy of the form of proxy or other communication which is specified in such request, with reasonable promptness after a tender to the Trustee of the material to be mailed and of payment, or provision for the payment, of the reasonable expenses of mailing, unless within five days after such tender the Trustee shall mail to such applicants and file with the Commission, together with a copy of the material to be mailed, a written statement to the effect that, in the opinion of the Trustee, such mailing would be contrary to the best interest of the Holders or would be in violation of applicable law. Such written statement shall specify the basis of such opinion. If the Commission, after opportunity for a hearing upon the objections specified in the written statement so filed, shall enter an order refusing to sustain any of such objections or if, after the entry of an order sustaining one or more of such objections, the Commission shall find, after notice and opportunity for hearing, that all the objections so sustained have been met and shall enter an order so declaring, the Trustee shall mail copies of such material to all such Holders with reasonable promptness after the entry of such order and the renewal of such tender; otherwise the Trustee shall be relieved of any obligation or duty to such applicants respecting their application.

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SECTION 703. Reports by Trustee.

        Any Trustee's report required pursuant to Section 313(a) of the Trust Indenture Act shall be dated as of May 15, and shall be transmitted within 60 days after May 15 of each year, commencing with the year 2002, by mail to all Holders, as their names and addresses appear in the Security Register. A copy of each such report shall, at the time of such transmission to Holders, be filed by the Trustee with each stock exchange or automated quotation system, as applicable, upon which any Securities are listed or traded, with the Commission and with the Partnership. The Partnership will notify the Trustee when any Securities are listed on any stock exchange or traded on any automated quotation system.

SECTION 704. Reports by Partnership.

        The Partnership shall:

ARTICLE VIII
CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE

SECTION 801. Partnership May Consolidate, Etc., Only on Certain Terms.

        The Partnership shall not consolidate with or merge into any other Person or sell, lease or transfer its properties and assets as, or substantially as, an entirety to, any Person, unless:

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SECTION 802. Successor Substituted.

        Upon any consolidation of the Partnership with, or merger of the Partnership into, any other Person or any sale, transfer or lease of the properties and assets of the Partnership as, or substantially as, an entirety in accordance with Section 801, the successor Person formed by such consolidation or into which the Partnership is merged or to which such sale, transfer or lease is made shall succeed to, and be substituted for, and may exercise every right and power of, the Partnership under this Indenture with the same effect as if such successor Person had been named originally as the Partnership herein, and thereafter, except in the case of a lease, the predecessor Person shall be relieved of all obligations and covenants under this Indenture and the Securities.

ARTICLE IX
SUPPLEMENTAL INDENTURES

SECTION 901. Supplemental Indentures Without Consent of Holders.

        Without the consent of any Holders, the Partnership, when authorized by a Board Resolution, and the Trustee, at any time and from time to time, may enter into one or more indentures supplemental hereto, in form satisfactory to the Trustee, for any of the following purposes:

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The Trustee is hereby authorized to join with the Partnership in the execution of any such supplemental indenture, to make any further appropriate agreements and stipulations which may be therein contained and to accept the conveyance, transfer, assignment, mortgage or pledge of any property thereunder, but the Trustee shall not be obligated to enter into any such supplemental indenture which affects the Trustee's own rights, duties or immunities under this Indenture or otherwise.

SECTION 902. Supplemental Indentures with Consent of Holders.

        With the consent of the Holders of not less than a majority in aggregate principal amount of the Outstanding Securities of all series affected by such supplemental indenture, by Act of said Holders delivered to the Partnership and the Trustee, the Partnership, when authorized by a Board Resolution, and the Trustee may enter into an indenture or indentures supplemental hereto for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this Indenture or of modifying in any manner the rights of the Holders of Securities of such series under this Indenture; provided, however, that no such supplemental indenture shall, without the consent of the Holder of each Outstanding Security affected thereby,

A supplemental indenture which changes or eliminates any covenant or other provision of this Indenture which has expressly been included solely for the benefit of one or more particular series of Securities, or which

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modifies the rights of the Holders of Securities of such series with respect to such covenant or other provision, shall be deemed not to affect the rights under this Indenture of the Holders of Securities of any other series.

        It shall not be necessary for any Act of Holders under this Section 902 to approve the particular form of any proposed supplemental indenture, but it shall be sufficient if such Act shall approve the substance thereof.

SECTION 903. Execution of Supplemental Indentures.

        In executing, or accepting the additional trusts created by, any supplemental indenture permitted by this Article or the modifications thereby of the trusts created by this Indenture, the Trustee shall be entitled to receive, and (subject to Section 601) shall be fully protected in relying upon, an Opinion of Counsel stating that the execution of such supplemental indenture is authorized or permitted by this Indenture. The Trustee may, but shall not be obligated to, enter into any such supplemental indenture which affects the Trustee's own rights, duties or immunities under this Indenture or otherwise.

SECTION 904. Effect of Supplemental Indentures.

        Upon the execution of any supplemental indenture under this Article, this Indenture shall be modified in accordance therewith, and such supplemental indenture shall form a part of this Indenture for all purposes; and every Holder of Securities theretofore or thereafter authenticated and delivered hereunder shall be bound thereby.

SECTION 905. Conformity with Trust Indenture Act.

        Every supplemental indenture executed pursuant to this Article shall conform to the requirements of the Trust Indenture Act as then in effect.

SECTION 906. Reference in Securities to Supplemental Indentures.

        Securities of any series authenticated and delivered after the execution of any supplemental indenture pursuant to this Article may, and shall if required by the Trustee, bear a notation in form approved by the Trustee as to any matter provided for in such supplemental indenture. If the Partnership shall so determine, new Securities of any series so modified as to conform, in the opinion of the Trustee and the Partnership, to any such supplemental indenture may be prepared and executed by the Partnership and authenticated and delivered by the Trustee in exchange for Outstanding Securities of such series.

ARTICLE X
COVENANTS

SECTION 1001. Payment of Principal, Premium and Interest.

        The Partnership covenants and agrees for the benefit of each series of Securities that it will duly and punctually pay the principal of and any premium and interest on the Securities of that series in accordance with the terms of the Securities and this Indenture.

SECTION 1002. Maintenance of Office or Agency.

        The Partnership will maintain in [                        ], and in each other Place of Payment for any series of Securities an office or agency where Securities of that series may be presented or surrendered for payment, where Securities of that series may be surrendered for registration of transfer or exchange and where notices and demands to or upon the Partnership in respect of the Securities of that series and this Indenture may be served. The Partnership will give prompt written notice to the Trustee of the location, and any change in the location, of such office or agency. If at any time the Partnership shall fail to maintain any such required office or agency or shall fail to furnish the Trustee with the address thereof, such presentations, surrenders, notices and demands may be made or served at the Corporate Trust Office of the Trustee, and the Partnership hereby appoints the Trustee as its agent to receive all such presentations, surrenders, notices and demands.

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        The Partnership may also from time to time designate one or more other offices or agencies where the Securities of one or more series may be presented or surrendered for any or all such purposes and may from time to time rescind such designations; provided, however, that no such designation or rescission shall in any manner relieve the Partnership of its obligation to maintain an office or agency in [                        ], and in each other Place of Payment for Securities of any series for such purposes. The Partnership will give prompt written notice to the Trustee of any such designation or rescission and of any change in the location of any such other office or agency.

        Except as otherwise specified with respect to a series of Securities as contemplated by Section 301, the Partnership hereby initially designates as the Place of Payment for each series of Securities The City and State of New York, and initially appoints the Trustee at its Corporate Trust Office as the Partnership's office or agency for each such purpose in such city.

SECTION 1003. Money for Securities Payments to Be Held in Trust.

        If the Partnership or any of its Subsidiaries shall at any time act as Paying Agent with respect to any series of Securities, it will, on or before each due date of the principal of and any premium or interest on any of the Securities of that series, segregate and hold in trust for the benefit of the Persons entitled thereto a sum sufficient to pay the principal and any premium and interest so becoming due until such sums shall be paid to such Persons or otherwise disposed of as herein provided and will promptly notify the Trustee of its action or failure so to act.

        Whenever the Partnership shall have one or more Paying Agents for any series of Securities, it will, on or prior to each due date of the principal of and any premium or interest on any Securities of that series, deposit with a Paying Agent a sum sufficient to pay the principal and any premium or interest so becoming due, such sum to be held in trust for the benefit of the Persons entitled to such principal, premium or interest, and (unless such Paying Agent is the Trustee) the Partnership will promptly notify the Trustee of its action or failure so to act. For purposes of this Section 1003, should a due date for principal of and any premium or interest on, or sinking fund payment with respect to any series of Securities not be on a Business Day, such payment shall be due on the next Business Day without any interest for the period from the due date until such Business Day.

        The Partnership will cause each Paying Agent for any series of Securities other than the Trustee to execute and deliver to the Trustee an instrument in which such Paying Agent shall agree with the Trustee, subject to the provisions of this Section 1003, that such Paying Agent will:

        The Partnership may at any time, for the purpose of obtaining the satisfaction and discharge of this Indenture or for any other purpose, pay, or by Partnership Order direct any Paying Agent to pay, to the Trustee all sums held in trust by the Partnership or such Paying Agent, such sums to be held by the Trustee upon the same trusts as those upon which such sums were held by the Partnership or such Paying Agent; and, upon such payment by any Paying Agent to the Trustee, such Paying Agent shall be released from all further liability with respect to such money.

        Subject to any applicable escheat or abandoned property laws, any money deposited with the Trustee or any Paying Agent, or then held by the Partnership, in trust for the payment of the principal of and any premium or interest on any Security of any series and remaining unclaimed for one year after such principal and any premium or interest has become due and payable shall be paid to the Partnership on Partnership Request, or (if then held by the Partnership) shall be discharged from such trust; and the Holder of such Security shall

46


thereafter, as an unsecured general creditor, look only to the Partnership for payment thereof, and all liability of the Trustee or such Paying Agent with respect to such trust money, and all liability of the Partnership as trustee thereof, shall thereupon cease; provided, however, that the Trustee or such Paying Agent, before being required to make any such repayment, may at the expense of the Partnership cause to be published once, in a newspaper published in the English language, customarily published on each Business Day and of general circulation in the Borough of Manhattan, The City of New York, notice that such money remains unclaimed and that, after a date specified therein, which shall not be less than 30 days from the date of such publication, any unclaimed balance of such money then remaining will be repaid to the Partnership.

SECTION 1004. Statement by Officers as to Default.

        Annually, within 150 days after the close of each fiscal year beginning with the fiscal year ending December 31, 2002, the Partnership will deliver to the Trustee a brief certificate (which need not include the statements set forth in Section 103) from the principal executive officer, principal financial officer or principal accounting officer of the General Partner of the Partnership as to his or her knowledge of the Partnership's compliance (without regard to any period of grace or requirement of notice provided herein) with all conditions and covenants under the Indenture and, if the Partnership shall be in Default, specifying all such Defaults and the nature and status thereof of which such officer has knowledge.

SECTION 1005. Existence.

        Subject to Article VIII, the Partnership will do or cause to be done all things necessary to preserve and keep in full force and effect its existence, rights (charter and statutory) and franchises; provided, however, that the Partnership shall not be required to preserve any such right or franchise if it shall determine that the preservation thereof is no longer desirable in the conduct of the business of the Partnership.

SECTION 1006. Limitations on Liens.

        The Partnership will not, nor will it permit any of its Subsidiaries to, create, assume, incur or suffer to exist any Lien upon any property or assets, whether owned or leased on the date of this Indenture or thereafter acquired, to secure any Debt of the Partnership or any other Person (other than the Securities issued hereunder), without in any such case making effective provision whereby all of the Securities Outstanding hereunder shall be secured equally and ratably with, or prior to, such Debt so long as such Debt shall be so secured. This restriction shall not apply to:

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        Notwithstanding the foregoing provisions of this Section 1006, the Partnership may, and may permit any of its Subsidiaries to, create, assume, incur or suffer to exist any Lien upon any property or assets to secure Debt of the Partnership or any Person (other than the Securities) that is not excepted by clauses (1) through (12), inclusive, of this Section 1006 without securing the Securities issued hereunder, provided that the aggregate principal amount of all Debt then Outstanding secured by such Lien and all similar Liens, together with all net sale proceeds from Sale-Leaseback Transactions (excluding Sale-Leaseback Transactions permitted by clauses (1) through (4), inclusive, of Section 1007), does not exceed 15% of Consolidated Net Tangible Assets.

SECTION 1007. Restriction of Sale-Leaseback Transaction.

        The Partnership will not, nor will it permit any of its Subsidiaries to, engage in a Sale-Leaseback Transaction, unless:

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        Notwithstanding the foregoing provisions of this Section 1007, the Partnership may, and may permit any of its Subsidiaries to, effect any Sale-Leaseback Transaction that is not excepted by clauses (1) through (4), inclusive, of this Section 1007; provided that the net sale proceeds from such Sale-Leaseback Transaction, together with the aggregate principal amount of then outstanding Debt (other than the Securities) secured by Liens upon any property or assets of the Partnership or its Subsidiaries not excepted by clauses (1) through (12), inclusive, of Section 1006, do not exceed 15% of the Consolidated Net Tangible Assets.

SECTION 1008. Waiver of Certain Covenants.

        The Partnership may omit in any particular instance to comply with any term, provision or condition set forth in Section 1005, 1006 or 1007 with respect to the Securities of any series if before the time for such compliance the Holders of at least a majority in aggregate principal amount of the Outstanding Securities of all affected series (voting as one class) shall, by Act of such Holders, either waive such compliance in such instance or generally waive compliance with such term, provision or condition, but no such waiver shall extend to or affect such term, provision or condition except to the extent so expressly waived, and, until such waiver shall become effective, the obligations of the Partnership and the duties of the Trustee in respect of any such term, provision or condition shall remain in full force and effect.

        A waiver which changes or eliminates any term, provision or condition of this Indenture which has expressly been included solely for the benefit of one or more particular series of Securities, or which modifies the rights of the Holders of Securities of such series with respect to such term, provision or condition, shall be deemed not to affect the rights under this Indenture of the Holders of Securities of any other series.

SECTION 1009. Additional Amounts.

        If the Securities of a series provide for the payment of additional amounts (as provided in Section 301(18)), at least 10 days prior to the first Interest Payment Date with respect to that series of Securities and at least 10 days prior to each date of payment of principal of, premium, if any, or interest on the Securities of that series if there has been a change with respect to the matters set forth in the below-mentioned Officers' Certificate, the Partnership shall furnish to the Trustee and the principal paying agent, if other than the Trustee, an Officers' Certificate instructing the Trustee and such paying agent whether such payment of principal of, premium, if any, or interest on the Securities of that series shall be made to holders of the Securities of that series without withholding or deduction for or on account of any tax, assessment or other governmental charge described in the Securities of that series. If any such withholding or deduction shall be required, then such Officers' Certificate shall specify by country the amount, if any, required to be withheld or deducted on such payments to such holders and shall certify the fact that additional amounts will be payable and the amounts so payable to each holder, and the Partnership shall pay to the Trustee or such paying agent the additional amounts required to be paid by this Section 1009. The Partnership covenants to indemnify the Trustee and any paying agent for, and to hold them harmless against, any loss, liability or expense reasonably incurred without negligence or bad faith on their part arising out of or in connection with actions taken or omitted by any of them in reliance on any Officers' Certificate furnished pursuant to this Section 1009.

        Whenever in this Indenture there is mentioned, in any context, the payment of the principal of or any premium, interest or any other amounts on, or in respect of, any Securities of any series, such mention shall be deemed to include mention of the payment of additional amounts provided by the terms of such series established hereby or pursuant hereto to the extent that, in such context, additional amounts are, were or would be payable in respect thereof pursuant to such terms, and express mention of the payment of additional amounts (if applicable) in any provision hereof shall not be construed as excluding the payment of additional amounts in those provisions hereof where such express mention is not made.

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ARTICLE XI
REDEMPTION OF SECURITIES

SECTION 1101. Applicability of Article.

        Securities of any series which are redeemable before their Stated Maturity shall be redeemable in accordance with their terms and (except as otherwise specified as contemplated by Section 301 for Securities of any series) in accordance with this Article.

SECTION 1102. Election to Redeem; Notice to Trustee.

        The election of the Partnership to redeem any Securities shall be evidenced by a Board Resolution. In case of any redemption at the election of the Partnership of less than all the Securities of any series, the Partnership shall, not less than 30 nor more than 60 days prior to the Redemption Date fixed by the Partnership (unless a shorter notice shall be satisfactory to the Trustee), notify the Trustee of such Redemption Date, of the principal amount of Securities of such series to be redeemed and, if applicable, of the tenor of the Securities to be redeemed. In the case of any redemption of Securities (1) prior to the expiration of any restriction on such redemption provided in the terms of such Securities or elsewhere in this Indenture, or (2) pursuant to an election of the Partnership which is subject to a condition specified in the terms of such Securities, the Partnership shall furnish the Trustee with an Officers' Certificate evidencing compliance with such restriction or condition.

SECTION 1103. Selection by Trustee of Securities to be Redeemed.

        If less than all the Securities of any series are to be redeemed (unless all the Securities of such series and of a specified tenor are to be redeemed), the particular Securities to be redeemed shall be selected not more than 45 days prior to the Redemption Date by the Trustee, from the Outstanding Securities of such series not previously called for redemption, by lottery for redemption of portions (equal to the minimum authorized denomination for Securities of that series or any integral multiple thereof) of the principal amount of Securities of such series of a denomination larger than the minimum authorized denomination for Securities of that series.

        The Trustee shall promptly notify the Partnership in writing of the Securities selected for redemption and, in the case of any Securities selected for partial redemption, the principal amount thereof to be redeemed. If the Securities of any series to be redeemed consist of Securities having different dates on which the principal is payable or different rates of interest, or different methods by which interest may be determined or have any other different tenor or terms, then the Partnership may, by written notice to the Trustee, direct that the Securities of such series to be redeemed shall be selected from among the groups of such Securities having specified tenor or terms and the Trustee shall thereafter select the particular Securities to be redeemed in the manner set forth in the preceding paragraph from among the group of such Securities so specified.

        For all purposes of this Indenture, unless the context otherwise requires, all provisions relating to the redemption of Securities shall relate, in the case of any Securities redeemed or to be redeemed only in part, to the portion of the principal amount of such Securities which has been or is to be redeemed.

SECTION 1104. Notice of Redemption.

        Notice of redemption shall be given by first-class mail (if international mail, by air mail), postage prepaid, mailed not less than 30 nor more than 60 days prior to the Redemption Date, to each Holder of Securities to be redeemed, at his address appearing in the Security Register.

        All notices of redemption shall state:

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        Notice of redemption of Securities to be redeemed shall be given by the Partnership or, at the Partnership's request, by the Trustee in the name and at the expense of the Partnership.

SECTION 1105. Deposit of Redemption Price.

        On or prior to any Redemption Date, the Partnership shall deposit with the Trustee or with a Paying Agent (or, if the Partnership is acting as its own Paying Agent, segregate and hold in trust as provided in Section 1003) an amount of money sufficient to pay the Redemption Price of, and (except if the Redemption Date shall be an Interest Payment Date) accrued interest on, all the Securities which are to be redeemed on that date.

SECTION 1106. Securities Payable on Redemption Date.

        Notice of redemption having been given as aforesaid, the Securities so to be redeemed shall, on the Redemption Date, become due and payable at the Redemption Price therein specified, and from and after such date (unless the Partnership shall default in the payment of the Redemption Price and accrued interest) such Securities shall cease to bear interest. Upon surrender of any such Security for redemption in accordance with said notice, such Security shall be paid by the Partnership at the Redemption Price, together with accrued interest to the Redemption Date; provided, however, that, unless otherwise specified as contemplated by Section 301, installments of interest whose Stated Maturity is on or prior to the Redemption Date shall be payable to the Holders of such Securities, or one or more Predecessor Securities, registered as such at the close of business on the relevant Record Dates according to their terms and the provisions of Section 307.

        If any Security called for redemption shall not be so paid upon surrender thereof for redemption, the principal and any premium shall, until paid, bear interest from the Redemption Date at the rate prescribed therefor in the Security.

SECTION 1107. Securities Redeemed in Part.

        Any Security which is to be redeemed only in part shall be surrendered at a Place of Payment therefor (with, if the Partnership or the Trustee so requires, due endorsement by, or a written instrument of transfer in form satisfactory to the Partnership and the Trustee duly executed by, the Holder thereof or his attorney duly authorized in writing), and the Partnership shall execute, and the Trustee shall authenticate and deliver to the Holder of such Security without service charge, a new Security or Securities of the same series and of like tenor, of any authorized denomination as requested by such Holder, in aggregate principal amount equal to and in exchange for the unredeemed portion of the principal of the Security so surrendered.

ARTICLE XII
SINKING FUNDS

SECTION 1201. Applicability of Article.

        The provisions of this Article shall be applicable to any sinking fund for the retirement of Securities of a series except as otherwise specified as contemplated by Section 301 for Securities of such series.

        The minimum amount of any sinking fund payment provided for by the terms of Securities of any series is herein referred to as a "mandatory sinking fund payment," and any payment in excess of such minimum amount provided for by the terms of Securities of any series is herein referred to as an "optional sinking fund payment." If provided for by the terms of Securities of any series, the cash amount of any sinking fund payment may be subject to reduction as provided in Section 1202. Each sinking fund payment shall be applied to the redemption of Securities of any series as provided for by the terms of Securities of such series.

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SECTION 1202. Satisfaction of Sinking Fund Payments with Securities.

        The Partnership (1) may deliver Outstanding Securities of a series (other than any previously called for redemption), and (2) may apply as a credit Securities of a series which have been redeemed either at the election of the Partnership pursuant to the terms of such Securities or through the application of permitted optional sinking fund payments pursuant to the terms of such Securities, in each case in satisfaction of all or any part of any sinking fund payment with respect to the Securities of such series required to be made pursuant to the terms of such Securities as provided for by the terms of such series; provided that such Securities have not been previously so credited. Such Securities shall be received and credited for such purpose by the Trustee at the Redemption Price specified in such Securities for redemption through operation of the sinking fund and the amount of such sinking fund payment shall be reduced accordingly.

SECTION 1203. Redemption of Securities for Sinking Fund.

        Not less than 45 days prior to each sinking fund payment date for any series of Securities (unless a shorter period shall be satisfactory to the Trustee), the Partnership will deliver to the Trustee an Officers' Certificate specifying the amount of the next ensuing sinking fund payment for that series pursuant to the terms of that series, the portion thereof, if any, which is to be satisfied by payment of cash and the portion thereof, if any, which is to be satisfied by delivering and crediting Securities of that series pursuant to Section 1202 and stating the basis for such credit and that such Securities have not been previously so credited, and will also deliver to the Trustee any Securities to be so delivered. Not less than 30 days before each such sinking fund payment date the Trustee shall select the Securities to be redeemed upon such sinking fund payment date in the manner specified in Section 1103 and cause notice of the redemption thereof to be given in the name of and at the expense of the Partnership in the manner provided in Section 1104. Such notice having been duly given, the redemption of such Securities shall be made upon the terms and in the manner stated in Sections 1106 and 1107.

ARTICLE XIII
DEFEASANCE

SECTION 1301. Applicability of Article.

        The provisions of this Article shall be applicable to each series of Securities except as otherwise specified as contemplated by Section 301 for Securities of such series.

SECTION 1302. Legal Defeasance.

        In addition to discharge of this Indenture pursuant to Section 401, the Partnership shall be deemed to have paid and discharged the entire indebtedness on all the Securities of such a series on the 91st day after the date of the deposit referred to in clause (1) below, and the provisions of this Indenture with respect to the Securities of such series shall no longer be in effect (except as to (i) rights of registration of transfer and exchange of Securities of such series and the Partnership's right of optional redemption, if any, (ii) substitution of mutilated, destroyed, lost or stolen Securities, (iii) rights of Holders of Securities to receive, solely from the trust fund described in Section 1304 and as more fully set forth in such Section, payments of principal thereof and interest thereon, upon the original stated due dates therefor or on the specified redemption dates therefor (but not upon acceleration), and remaining rights of the holders to receive mandatory sinking fund payments, if any, (iv) the rights, obligations, duties and immunities of the Trustee hereunder, and the Partnership's obligations in connection therewith (including, but not limited to, Section 607), (v) the rights, if any, to convert or exchange the Securities of such series, (vi) the rights of the Holders of Securities of such series as beneficiaries hereof with respect to the property so deposited with the Trustee payable to all or any of them, and (vii) the obligations of the Partnership under Section 1002), and the Trustee, at the expense of the Partnership, shall, upon a Partnership Request, execute proper instruments acknowledging the same, if the conditions set forth below are satisfied (hereinafter, "defeasance"):

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        For this purpose, such defeasance means that the Partnership and any other obligor upon the Securities of such series shall be deemed to have paid and discharged the entire debt represented by the Securities of such series, which shall thereafter be deemed to be "Outstanding" only for the purposes of Section 1304 and the rights and obligations referred to in clauses (i) through (vii), inclusive, of the first paragraph of this Section 1302, and to have satisfied all its other obligations under the Securities of such series and this Indenture insofar as the Securities of such series are concerned.

        Notwithstanding the foregoing, if an Event of Default specified in Section 501(4) or 501(5), or an event which with lapse of time would become such an Event of Default, shall occur during the period ending on the 91st day after the date of the deposit referred to in clause (1) or, if longer, ending on the day following the expiration of the longest preference period applicable to the Partnership in respect of such deposit, then, effective upon such occurrence, the defeasance pursuant to this Section 1302 and such deposit shall be rescinded and annulled, and the Partnership, the Trustee and the Holders of the Securities of such series shall be restored to their former positions.

SECTION 1303. Covenant Defeasance.

        The Partnership and any other obligor shall be released on the 91st day after the date of the deposit referred to in clause (1) below from its obligations under Sections 704, 801, 1005, 1006 and 1007 with respect to the Securities of any series on and after the date the conditions set forth below are satisfied (hereinafter,

53


"covenant defeasance"), and the Securities of such series shall thereafter be deemed to be not "Outstanding" for the purposes of any request, demand, authorization, direction, notice, waiver, consent or declaration or other action or Act of Holders (and the consequences of any thereof) in connection with such covenants, but shall continue to be deemed Outstanding for all other purposes hereunder. For this purpose, such covenant defeasance means that, with respect to the Securities of such series, the Partnership may omit to comply with and shall have no liability in respect of any term, condition or limitation set forth in any such Section, whether directly or indirectly by reason of any reference elsewhere herein to such Section or by reason of any reference in such Section to any other provision herein or in any other document and such omission to comply shall not constitute a Default or an Event of Default under Section 501, but, except as specified above, the remainder of this Indenture and the Securities of such series shall be unaffected thereby. The following shall be the conditions to application of this Section 1303:

        Notwithstanding the foregoing, if an Event of Default specified in Section 501(4) or 501(5), or an event which with lapse of time would become such an Event of Default, shall occur during the period ending on the 91st day after the date of the deposit referred to in clause (1) or, if longer, ending on the day following the expiration of the longest preference period applicable to the Partnership in respect of such deposit, then, effective upon such occurrence, the defeasance pursuant to this Section 1303 and such deposit shall be rescinded

54

and annulled, and the Partnership, the Trustee and the Holders of the Securities of such series shall be restored to their former positions.

SECTION 1304. Application by Trustee of Funds Deposited for Payment of Securities.

        Subject to the provisions of the last paragraph of Section 1003, all moneys or U.S. Government Obligations (including proceeds thereof) deposited with the Trustee pursuant to Section 1302 or 1303 (and all funds earned on such moneys or U.S. Government Obligations) shall be held in trust and applied by it, in accordance with the provisions of such Securities and this Indenture, to the payment, either directly or through any Paying Agent (including the Partnership acting as its own Paying Agent), to the Holders of the particular Securities of such series for the payment or redemption of which such moneys have been deposited with the Trustee, of all sums due and to become due thereon for principal and any premium and interest; but such money need not be segregated from other funds except to the extent required by law. Subject to Sections 1302 and 1303, the Trustee shall promptly pay to the Partnership upon request any excess moneys held by it at any time.

SECTION 1305. Repayment to Partnership.

        The Trustee and any Paying Agent promptly shall pay or return to the Partnership upon Partnership Request any money and U.S. Government Obligations held by them at any time that are not required for the payment of the principal of, premium, if any, and any interest on the Securities of any series for which money or U.S. Government Obligations have been deposited pursuant to Section 1302 or 1303.

        The provisions of the last paragraph of Section 1003 shall apply to any money held by the Trustee or any Paying Agent under this Article that remains unclaimed for one year after the Maturity of any series of Securities for which money or U.S. Government Obligations have been deposited pursuant to Section 1302 or 1303.

* * *

        This instrument may executed in any number of counterparts, each of which so executed shall be deemed to be an original, but all such counterparts shall together constitute but one and the same instrument.

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        IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be duly executed, all as of the day and year first above written.

    TC PIPELINES, LP

 
 
By:
TC PipeLines GP, Inc.,
Its General Partner

 
 
By:

 
 
Name:

 
 
Title:

 
 
[                                                 ], as Trustee

 
 
By:

 
 
Name:

 
 
Title:

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EXHIBIT 4.2

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EXHIBIT 4.3

TC PIPELINES, LP,

ISSUER

AND

[                                        ],

TRUSTEE

INDENTURE

DATED AS OF [                        ] [    ], [            ]

SUBORDINATED DEBT SECURITIES

TC PIPELINES, LP

Reconciliation and tie between Trust Indenture Act of 1939, as amended,

and Indenture, dated as of [                        ] [    ], [            ]

Trust Indenture
Act Section
    
   Indenture Section
§ 310 (a) (1)       609
  (a) (2)       609
  (a) (3)       Not Applicable
  (a) (4)       Not Applicable
  (b)         608; 610
§ 311 (a)         613
  (b)         613
§ 312 (a)         701; 702
  (b)         702
  (c)         702
§ 313 (a)         703
  (b)         *
  (c)         *
  (d)         703
§ 314 (a)         704
  (a) (4)       104; 1004
  (b)         Not Applicable
  (c) (1)       101
  (c) (2)       101; 102
  (c) (3)       Not Applicable
  (d)         Not Applicable
  (e)         102
§ 315 (a)         601
  (b)         602
  (c)         601
  (d)         601
  (e)         514
§ 316 (a)         101
  (a) (1) (A)       502; 512
  (a) (1) (B)       513
  (a) (2)       Not Applicable
  (b)         508
  (c)         104
§ 317 (a) (1)       503
  (a) (2)       504
  (b)         1003
§318 (a)         107
       

        NOTE: This reconciliation and tie shall not, for any purpose, be deemed to be a part of the Indenture.

TABLE OF CONTENTS

 
    
   PAGE

ARTICLE I Definitions And Other Provisions Of General Application
 
 
  SECTION 101.   Definitions.   1
  SECTION 102.   Incorporation by Reference of Trust Indenture Act.   6
  SECTION 103.   Compliance Certificates and Opinions.   7
  SECTION 104.   Form of Documents Delivered to Trustee.   7
  SECTION 105.   Acts of Holders; Record Dates.   7
  SECTION 106.   Notices, Etc., to Trustee and Partnership.   8
  SECTION 107.   Notice to Holders; Waiver.   8
  SECTION 108.   Conflict with Trust Indenture Act.   9
  SECTION 109.   Effect of Headings and Table of Contents.   9
  SECTION 110.   Successors and Assigns.   9
  SECTION 111.   Separability Clause.   9
  SECTION 112.   Benefits of Indenture.   9
  SECTION 113.   Governing Law.   9
  SECTION 114.   Legal Holidays.   9
  SECTION 115.   Securities in a Composite Currency, Currency Unit or Foreign Currency.   10
  SECTION 116.   Judgment Currency.   10
  SECTION 117.   Language of Notices, Etc.   10
  SECTION 118.   Non-Recourse to the General Partner; No Personal Liability of Officers, Directors, Employees or Partners.   11

ARTICLE II Security Forms
 
 
  SECTION 201.   Forms Generally.   11
  SECTION 202.   Form of Face of Security.   11
  SECTION 203.   Form of Reverse of Security.   13
  SECTION 204.   Global Securities.   17
  SECTION 205.   Form of Trustee's Certificate of Authentication.   18

ARTICLE III The Securities
 
 
  SECTION 301.   Amount Unlimited; Issuable in Series.   18
  SECTION 302.   Denominations.   20
  SECTION 303.   Execution, Authentication, Delivery and Dating.   20
  SECTION 304.   Temporary Securities.   22
  SECTION 305.   Registration, Registration of Transfer and Exchange.   22
  SECTION 306.   Mutilated, Destroyed, Lost and Stolen Securities.   24
  SECTION 307.   Payment of Interest; Interest Rights Preserved.   24
  SECTION 308.   Persons Deemed Owners.   25
  SECTION 309.   Cancellation.   25
  SECTION 310.   Computation of Interest.   26
  SECTION 311.   CUSIP Numbers.   26

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ARTICLE IV Satisfaction And Discharge
 
 
  SECTION 401.   Satisfaction and Discharge of Indenture.   26
  SECTION 402.   Application of Trust Money.   27

ARTICLE V Remedies
 
 
  SECTION 501.   Events of Default.   27
  SECTION 502.   Acceleration of Maturity; Rescission and Annulment.   28
  SECTION 503.   Collection of Indebtedness and Suits for Enforcement by Trustee.   28
  SECTION 504.   Trustee May File Proofs of Claim.   29
  SECTION 505.   Trustee May Enforce Claims Without Possession of Securities.   29
  SECTION 506.   Application of Money Collected.   29
  SECTION 507.   Limitation on Suits.   30
  SECTION 508.   Unconditional Right of Holders to Receive Principal, Premium and Interest.   30
  SECTION 509.   Restoration of Rights and Remedies.   30
  SECTION 510.   Rights and Remedies Cumulative.   31
  SECTION 511.   Delay or Omission Not Waiver.   31
  SECTION 512.   Control by Holders.   31
  SECTION 513.   Waiver of Past Defaults.   31
  SECTION 514.   Undertaking for Costs.   31
  SECTION 515.   Waiver of Usury, Stay or Extension Laws.   32

ARTICLE VI The Trustee
 
 
  SECTION 601.   Certain Duties and Responsibilities.   32
  SECTION 602.   Notice of Defaults.   33
  SECTION 603.   Certain Rights of Trustee.   33
  SECTION 604.   Not Responsible for Recitals or Issuance of Securities.   34
  SECTION 605.   May Hold Securities.   34
  SECTION 606.   Money Held in Trust.   34
  SECTION 607.   Compensation and Reimbursement.   34
  SECTION 608.   Disqualification; Conflicting Interests.   35
  SECTION 609.   Corporate Trustee Required; Eligibility.   35
  SECTION 610.   Resignation and Removal; Appointment of Successor.   35
  SECTION 611.   Acceptance of Appointment by Successor.   36
  SECTION 612.   Merger, Conversion, Consolidation or Succession to Business.   37
  SECTION 613.   Preferential Collection of Claims Against Partnership.   37
  SECTION 614.   Appointment of Authenticating Agent.   38

ARTICLE VII Holders' Lists And Reports By Trustee And Partnership
 
 
  SECTION 701.   Partnership to Furnish Trustee Names and Addresses of Holders.   39
  SECTION 702.   Preservation of Information; Communications to Holders.   39

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   PAGE
  SECTION 703.   Reports by Trustee.   40
  SECTION 704.   Reports by Partnership.   40

ARTICLE VIII Consolidation, Merger, Conveyance, Transfer Or Lease
 
 
  SECTION 801.   Partnership May Consolidate, Etc., Only on Certain Terms.   40
  SECTION 802.   Successor Substituted.   41

ARTICLE IX Supplemental Indentures
 
 
  SECTION 901.   Supplemental Indentures Without Consent of Holders.   41
  SECTION 902.   Supplemental Indentures with Consent of Holders.   42
  SECTION 903.   Execution of Supplemental Indentures.   43
  SECTION 904.   Effect of Supplemental Indentures.   43
  SECTION 905.   Conformity with Trust Indenture Act.   43
  SECTION 906.   Reference in Securities to Supplemental Indentures.   43

ARTICLE X Covenants
 
 
  SECTION 1001.   Payment of Principal, Premium and Interest.   43
  SECTION 1002.   Maintenance of Office or Agency.   43
  SECTION 1003.   Money for Securities Payments to Be Held in Trust.   44
  SECTION 1004.   Statement by Officers as to Default.   45
  SECTION 1005.   Existence.   45
  SECTION 1006.   Waiver of Certain Covenants.   45
  SECTION 1007.   Additional Amounts.   45

ARTICLE XI Redemption Of Securities
 
 
  SECTION 1101.   Applicability of Article.   46
  SECTION 1102.   Election to Redeem; Notice to Trustee.   46
  SECTION 1103.   Selection by Trustee of Securities to be Redeemed.   46
  SECTION 1104.   Notice of Redemption.   47
  SECTION 1105.   Deposit of Redemption Price.   47
  SECTION 1106.   Securities Payable on Redemption Date.   47
  SECTION 1107.   Securities Redeemed in Part.   47

ARTICLE XII Sinking Funds
 
 
  SECTION 1201.   Applicability of Article.   48
  SECTION 1202.   Satisfaction of Sinking Fund Payments with Securities.   48
  SECTION 1203.   Redemption of Securities for Sinking Fund.   48

ARTICLE XIII Defeasance
 
 
  SECTION 1301.   Applicability of Article.   48
  SECTION 1302.   Legal Defeasance.   48
  SECTION 1303.   Covenant Defeasance.   50
  SECTION 1304.   Application by Trustee of Funds Deposited for Payment of Securities.   51
         

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  SECTION 1305.   Repayment to Partnership.   51

ARTICLE XIV Subordination of Securities
 
 
  SECTION 1401.   Securities Subordinated to Senior Debt.   51
  SECTION 1402.   Distribution on Dissolution, Liquidation and Reorganization; Subrogation of Securities.   52
  SECTION 1403.   Payments on Securities Permitted.   53
  SECTION 1404.   Authorization of Holders of Securities to Trustee to Effect Subordination.   54
  SECTION 1405.   Notices to Trustee.   54
  SECTION 1406.   Trustee as Holder of Senior Debt.   54
  SECTION 1407.   Modification of Terms of Senior Debt.   54

v

INDENTURE

Parties:

        INDENTURE, dated as of [                ] [        ], [            ], between TC PIPELINES, LP, a Delaware limited partnership (herein called the "Partnership"), having its principal office at 110 Turnpike Road, Suite 203, Westborough, Massachusetts 01581 and [                        ], as trustee (herein called the "Trustee").

RECITALS OF THE PARTNERSHIP:

        The Partnership has duly authorized the execution and delivery of this Indenture to provide for the issuance from time to time of its unsecured subordinated debentures, notes or other evidences of indebtedness (herein called the "Securities"), to be issued in one or more series as in this Indenture provided.

        All things necessary to make this Indenture a valid agreement of the Partnership, in accordance with its terms, have been done.

        This Indenture is subject to the provisions of the Trust Indenture Act that are required to be a part of this Indenture and, to the extent applicable, shall be governed by such provisions.

        Now, Therefore, This Indenture Witnesseth:

        For and in consideration of the premises and the purchase of the Securities by the Holders thereof, it is mutually covenanted and agreed, for the equal and proportionate benefit of all Holders of the Securities or of series thereof, as follows:

ARTICLE I
DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

SECTION 101. Definitions.

        For all purposes of this Indenture, except as otherwise expressly provided or unless the context otherwise requires:

        Certain terms, used principally in Article VI, are defined in that Article.

        "Act," when used with respect to any Holder, has the meaning specified in Section 105.

        "Affiliate" of any specified Person means any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such specified Person. For the purposes of this definition, "control" when used with respect to any specified Person means the power to direct the management and


policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise, and the terms "controlling" and "controlled" have meanings correlative to the foregoing.

        "Authenticating Agent" means any Person authorized by the Trustee to act on behalf of the Trustee to authenticate Securities.

        "Banking Day" means, with respect to any city, any date on which commercial banks are open for business in that city.

        "Bankruptcy Law" means Title 11, U.S. Code, or any similar federal or state law for the relief of debtors or the protection of creditors.

        "Board of Directors" means the board of directors of the General Partner, or the executive or any other committee of that board duly authorized to act in respect thereof. If the Partnership shall change its form of entity to other than a limited partnership, the references to officers or the Board of Directors of the General Partner shall mean the officers or the Board of Directors (or other comparable governing body), respectively, of the Partnership.

        "Board Resolution" means a copy of a resolution certified by the Secretary or an Assistant Secretary of the General Partner, the principal financial officer of the General Partner or any other authorized officer of the General Partner or a person duly authorized by any of them, to have been duly adopted by the Board of Directors and to be in full force and effect on the date of such certification, and delivered to the Trustee. Where any provision of this Indenture refers to action to be taken pursuant to a Board Resolution (including the establishment of any series of the Securities and the forms and terms thereof), such action may be taken by any committee, officer or employee of the Partnership authorized to take such action by the Board of Directors as evidenced by a Board Resolution.

        "Business Day," when used with respect to any Place of Payment or other location, means, except as otherwise provided as contemplated by Section 301 with respect to any series of Securities, each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in that Place of Payment or other location are authorized or obligated by law, executive order or regulation to close.

        "Capital Interests" means any and all shares, interests, participations, rights or other equivalents (however designated) of capital stock, including, without limitation, with respect to partnerships, partnership interests (whether general or limited) and any other interest or participation that confers on a Person the right to receive a share of the profits and losses of, or distributions of assets of, such partnership.

        "Commission" means the Securities and Exchange Commission, as from time to time constituted, created under the Exchange Act or, if at any time after the execution of this instrument such Commission is not existing and performing the duties now assigned to it under the Trust Indenture Act, then the body performing such duties at such time.

        "Corporate Trust Office" means the office of the Trustee at which at any particular time its corporate trust business shall be principally administered in [                        ], and which, at the date hereof is [                        ].

        "corporation" includes corporations, associations, limited liability companies, joint-stock companies and business trusts.

        "covenant defeasance" has the meaning specified in Section 1303.

        "CUSIP" means the Committee on Uniform Securities Identification Procedures.

        "Custodian" means any receiver, trustee, assignee, liquidator or similar official under any Bankruptcy Law.

        "Debt" means any obligation created or assumed by any Person for the repayment of money borrowed, and any purchase money obligation created or assumed by such Person.

        "Default" means, with respect to a series of Securities, any event that is, or after notice or lapse of time or both would be, an Event of Default.

        "Defaulted Interest" has the meaning specified in Section 307.

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        "defeasance" has the meaning specified in Section 1302.

        "Definitive Security" means a Security other than a Global Security or a temporary Security.

        "Depositary" means, with respect to Securities of any series issuable or issued in whole or in part in the form of one or more Global Securities, a clearing agency registered under the Exchange Act that is designated to act as Depositary for such Securities as contemplated by Section 301, until a successor Depositary shall have become such pursuant to the applicable provisions of this Indenture, and thereafter shall mean or include each Person which is then a Depositary hereunder, and if at any time there is more than one such Person, shall be a collective reference to such Persons.

        "Dollar" or "$" means the coin or currency of the United States of America as at the time of payment is legal tender for the payment of public and private debts.

        "Event of Default" has the meaning specified in Section 501.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended from time to time, and any statute successor thereto.

        "Foreign Currency" means a currency used by the government of a country other than the United States of America.

        "GAAP" means generally accepted accounting principles in the United States set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other entity as may be approved by a significant segment of the accounting profession of the United States, as in effect from time to time.

        "General Partner" means the person serving as such under the Partnership Agreement, which, on the date hereof, is TC PipeLines GP, Inc., a Delaware corporation.

        "Global Security" means a Security in global form that evidences all or part of a series of Securities and is authenticated and delivered to, and registered in the name of, the Depositary for the Securities of such series or its nominee.

        "Holder" means a Person in whose name a Security is registered in the Security Register.

        "Indenture" means this instrument as originally executed or as it may from time to time be supplemented or amended by one or more indentures supplemental hereto entered into pursuant to the applicable provisions hereof, including, for all purposes of this instrument, and any such supplemental indenture, the provisions of the Trust Indenture Act that are deemed to be a part of and govern this instrument and any such supplemental indenture, respectively. The term "Indenture" also shall include the terms of particular series of Securities established as contemplated by Section 301.

        "interest," when used with respect to an Original Issue Discount Security which by its terms bears interest only after Maturity, means interest payable after Maturity.

        "Interest Payment Date," when used with respect to any Security, means the Stated Maturity of an installment of interest on such Security.

        "mandatory sinking fund payment" has the meaning specified in Section 1201.

        "Maturity," when used with respect to any Security, means the date on which the principal of such Security or an installment of principal becomes due and payable as therein or herein provided, whether at the Stated Maturity or by declaration of acceleration, call for redemption or otherwise.

        "Notice of Default" means a written notice of the kind specified in Section 501(3).

        "Officers' Certificate" means a certificate signed by any two officers of the General Partner (or if the Partnership shall change its form of entity to other than a limited partnership, by Persons or officers, members, agents and the like positions comparable to those of the foregoing nature, as applicable), and delivered to the Trustee. One of the officers or such other Persons (as applicable) signing an Officers' Certificate given pursuant

3


to Section 1004 shall be the principal executive, financial or accounting officer of the General Partner (or if the Partnership shall change its form of entity to other than a limited partnership, by Persons or officers, members, agents and the like positions comparable to those of the foregoing nature, as applicable).

        "Opinion of Counsel" means a written opinion of counsel, who may be an employee of or counsel for the Partnership, the General Partner or an Affiliate of the General Partner and who shall be reasonably acceptable to the trustee.

        "Original Issue Discount Security" means any Security which provides for an amount less than the stated principal amount thereof to be due and payable upon a declaration of acceleration of the Maturity thereof pursuant to Section 502.

        "Outstanding," when used with respect to Securities, means, as of the date of determination, all Securities theretofore authenticated and delivered under this Indenture, except:

provided, however, that in determining whether the Holders of the requisite principal amount of the Outstanding Securities have given any request, demand, authorization, direction, notice, consent or waiver hereunder, (A) the principal amount of an Original Issue Discount Security that shall be deemed to be Outstanding shall be the amount of the principal thereof that would be due and payable as of the date of such determination upon acceleration of the Maturity thereof on such date pursuant to Section 502, (B) the principal amount of a Security denominated in one or more currencies or currency units other than U.S. dollars shall be the U.S. dollar equivalent of such currencies or currency units, determined in the manner provided as contemplated by Section 301 on the date of original issuance of such Security or by Section 115, if not otherwise so provided pursuant to Section 301, of the principal amount (or, in the case of an Original Issue Discount Security, the U.S. dollar equivalent (as so determined) on the date of original issuance of such Security, of the amount determined as provided in clause (A) above) of such Security, and (C) Securities owned by the Partnership or any other obligor upon the Securities or any Affiliate of the Partnership or of such other obligor shall be disregarded and deemed not to be Outstanding, except that, in determining whether the Trustee shall be protected in relying upon any such request, demand, authorization, direction, notice, consent or waiver, only Securities which the Trustee knows to be so owned shall be so disregarded. Securities so owned as described in clause (C) of the immediately preceding sentence which have been pledged in good faith may be regarded as Outstanding if the pledgee establishes to the satisfaction of the Trustee the pledgee's right so to act with respect to such Securities and that the pledgee is not the Partnership or any other obligor upon the Securities or any Affiliate of the Partnership or of such other obligor.

        "Partnership" means the Person named as the "Partnership" in the first paragraph of this instrument until a successor Person shall have become such pursuant to the applicable provisions of this Indenture, and thereafter "Partnership" shall mean such successor Person.

4


        "Partnership Agreement" means the Agreement of Limited Partnership of the Partnership as in effect from time to time.

        "Partnership Request" or "Partnership Order" means a written request or order delivered to the Trustee and signed in the name of the Partnership by any two officers of the General Partner, or if the Partnership shall change its form of entity to other than a limited partnership, by Persons or officers, members, agents and the like positions comparable to those of the foregoing nature, as applicable.

        "Paying Agent" means any Person authorized by the Partnership to pay the principal of and any premium or interest on any Securities on behalf of the Partnership.

        "Periodic Offering" means an offering of Securities of a series from time to time, the specific terms of which Securities, including, without limitation, the rate or rates of interest or formula for determining the rate or rates of interest thereon, if any, the Stated Maturity or Stated Maturities thereof, the original issue date or dates thereof, the redemption provisions, if any, with respect thereto, and any other terms specified as contemplated by Section 301 with respect thereto, are to be determined by the Partnership upon the issuance of such Securities.

        "Person" means any individual, corporation, partnership, joint venture, limited liability company, association, joint-stock company, trust, other entity, unincorporated organization or government, or any agency or political subdivision thereof.

        "Place of Payment," when used with respect to the Securities of any series, means, unless otherwise specifically provided for with respect to such series as contemplated by Section 301, the office or agency of the Partnership in The City of New York and such other place or places where, subject to the provisions of Section 1002, the principal of and any premium and interest on the Securities of that series are payable as contemplated by Section 301.

        "Predecessor Security" of any particular Security means every previous Security evidencing all or a portion of the same Debt as that evidenced by such particular Security; and, for the purposes of this definition, any Security authenticated and delivered under Section 306 in exchange for or in lieu of a mutilated, destroyed, lost or stolen Security shall be deemed to evidence the same debt as the mutilated, destroyed, lost or stolen Security.

        "Redemption Date," when used with respect to any Security to be redeemed, means the date fixed for such redemption by or pursuant to this Indenture.

        "Redemption Price," when used with respect to any Security to be redeemed, means the price at which it is to be redeemed pursuant to this Indenture.

        "Regular Record Date" for the interest payable on any Interest Payment Date on the Securities of any series means the date specified for that purpose as contemplated by Section 301.

        "Responsible Officer," when used with respect to the Trustee, means any officer of the Trustee within the corporate trust department, including any Vice President, assistant secretary, assistant treasurer, assistant cashier, trust officer, assistant trust officer or assistant controller assigned to the Corporate Trust Office, or any other officer of the Trustee customarily performing functions similar to those performed by any of the above designated officers and also means, with respect to a particular corporate trust matter, any other officer of the Trustee to whom such matter is referred because of his knowledge of and familiarity with the particular subject, and who shall have direct responsibility for the administration of this Indenture.

        "Securities" has the meaning stated in the first recital of this Indenture and more particularly means any Securities authenticated and delivered under this Indenture.

        "Security Register" and "Security Registrar" have the respective meanings specified in Section 305.

        "Senior Debt" of the Partnership, unless otherwise provided with respect to the Securities of a series as contemplated by Section 301, means (1) all Debt of the Partnership, whether currently outstanding or hereafter issued, unless, by the terms of the instrument creating or evidencing such Debt, it is provided that such Debt is not superior in right of payment to the Securities or to other Debt which is pari passu with or subordinated to the Securities, and (2) any modifications, refunding, deferrals, renewals or extensions of any such Debt or

5


securities, notes or other evidence of Debt issued in exchange for such Debt; provided that in no event shall "Senior Debt" include (a) Debt of the Partnership owed or owing to any Subsidiary of the Partnership or any officer, director or employee of the Partnership or any Subsidiary of the Partnership, (b) Debt to trade creditors or (c) any liability for taxes owed or owing by the Partnership.

        "Special Record Date" for the payment of any Defaulted Interest means a date fixed by the Trustee pursuant to Section 307.

        "Stated Maturity," when used with respect to any Security or any installment of principal thereof or interest thereon, means the date specified in such Security as the fixed date on which the principal of such Security or such installment of principal or interest is due and payable.

        "Subsidiary" of any Person means (i) any partnership of which more than 50% of the Capital Interests (considering all partners' Capital Interests as a single class) is at the time owned or controlled, directly or indirectly, by such Person or one or more of the other Subsidiaries of such Person or combination thereof, or (ii) any corporation, association or other business entity of which more than 50% of the total voting power of the Capital Interests entitled (without regard to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof is at the time owned or controlled, directly or indirectly, by such Person or one or more of the other Subsidiaries of such Person or combination thereof.

        "Trust Indenture Act" means the Trust Indenture Act of 1939 as in force at the date as of which this instrument was executed, except as otherwise provided in Section 905; provided, however, that if the Trust Indenture Act of 1939 is amended after such date, "Trust Indenture Act" means, to the extent required by any such amendment, the Trust Indenture Act of 1939 as so amended.

        "Trustee" means the Person named as the "Trustee" in the first paragraph of this instrument until a successor Trustee shall have become such pursuant to the applicable provisions of this Indenture, and thereafter "Trustee" shall mean or include each Person who is then a Trustee hereunder, and if at any time there is more than one such Person, "Trustee" as used with respect to the Securities of any series shall mean each Trustee with respect to Securities of that series.

        "U.S. Government Obligations" means securities which are (i) direct obligations of the United States for the payment of which its full faith and credit is pledged, or (ii) obligations of a Person controlled or supervised by and acting as an agency or instrumentality of the United States, the payment of which is unconditionally guaranteed as a full faith and credit obligation by the United States, each of which are not callable or redeemable at the option of the issuer thereof.

        "Vice President," when used with respect to the Partnership, means any vice president of the General Partner, or when used with respect to the Trustee, means any vice president of the Trustee.

SECTION 102. Incorporation by Reference of Trust Indenture Act.

        Whenever this Indenture refers to a provision of the Trust Indenture Act, the provision is incorporated by reference in and made a part of this Indenture. The following Trust Indenture Act terms used in this Indenture have the following meanings:

        "commission" means the Commission.

        "indenture securities" means the Securities.

        "indenture security holder" means a Holder.

        "indenture to be qualified" means this Indenture.

        "indenture trustee" or "institutional trustee" means the Trustee.

        "obligor" on the indenture securities means the Partnership or any other obligor on the indenture securities.

6


        All terms used in this Indenture that are defined by the Trust Indenture Act, defined by a Trust Indenture Act reference to another statute or defined by a Commission rule under the Trust Indenture Act have the meanings so assigned to them.

SECTION 103. Compliance Certificates and Opinions.

        Upon any application or request by the Partnership to the Trustee to take any action under any provision of this Indenture, the Partnership shall furnish to Trustee an Officers' Certificate stating that all conditions precedent, if any, provided for in this Indenture relating to the proposed action have been with and an Opinion of Counsel stating that in the opinion of such counsel all such conditions precedent, if any, have been complied with, except that in the case of any such application or request as to which the furnishing of such documents is specifically required by any provision of this Indenture relating to such particular application or request, no additional certificate or opinion need be furnished except as required under Section 314(c) of the Trust Indenture Act.

        Every certificate or opinion with respect to compliance with a condition or covenant provided for in this Indenture (except for certificates provided for in Section 1004) shall include:

SECTION 104. Form of Documents Delivered to Trustee.

        In any case where several matters are required to be certified by, or covered by an opinion of, any specified Person, it is not necessary that all such matters be certified by, or covered by the opinion of, only one such Person, or that they be so certified or covered by only one document, but one such Person may certify or give an opinion with respect to some matters and one or more other such Persons as to other matters, and any such Person may certify or give an opinion as to such matters in one or several documents.

        Any certificate or opinion of an officer of the Partnership or the General Partner may be based, insofar as it relates to legal matters, upon a certificate or opinion of, or representations by, counsel, unless such officer knows, or in the exercise of reasonable care should know, that the certificate or opinion or representations with respect to the matters upon which his certificate or opinion is based are erroneous. Any such certificate or opinion of counsel may be based, insofar as it relates to factual matters, upon a certificate or opinion of, or representations by, an officer or officers of the Partnership or the General Partner stating that the information with respect to such factual matters is in the possession of the Partnership or the General Partner, unless such counsel knows that the certificate or opinion or representations with respect to such matters are erroneous.

        Where any Person is required to make, give or execute two or more applications, requests, consents, certificates, statements, opinions or other instruments under this Indenture, they may, but need not, be consolidated and form one instrument.

SECTION 105. Acts of Holders; Record Dates.

        Any request, demand, authorization, direction, notice, consent, waiver or other action provided or permitted by this Indenture to be given or taken by Holders may be embodied in and evidenced by one or more instruments of substantially similar tenor signed (either physically or by means of a facsimile or an electronic transmission, provided that such electronic transmission is transmitted through the facilities of a Depositary) by such Holders in person or by an agent duly appointed in writing; and, except as herein otherwise expressly

7


provided, such action shall become effective when such instrument or instruments are delivered (either physically or by means of a facsimile or an electronic transmission, provided that such electronic transmission is transmitted through the facilities of a Depositary) to the Trustee and, where it is hereby expressly required, to the Partnership. Such instrument or instruments (and the action embodied therein and evidenced thereby) are herein sometimes referred to as the "Act" of the Holders signing such instrument or instruments. Proof of execution of any such instrument or of a writing appointing any such agent shall be sufficient for any purpose of this Indenture and (subject to Section 315 of the Trust Indenture Act) conclusive in favor of the Trustee and the Partnership, if made in the manner provided in this Section 105.

        The fact and date of the execution by any Person of any such instrument or writing may be proved by the affidavit of a witness of such execution or by a certificate of a notary public or other officer authorized by law to take acknowledgments of deeds, certifying that the individual signing such instrument or writing acknowledged to him the execution thereof. Where such execution is by a signer acting in a capacity other than his individual capacity, such certificate or affidavit shall also constitute sufficient proof of his authority. The fact and date of the execution of any such instrument or writing, or the authority of the Person executing the same, may also be proved in any other manner which the Trustee deems sufficient.

        The ownership, principal amount and serial numbers of Securities held by any Person, and the date of commencement of such Person's holding the same, shall be proved by the Security Register.

        Any request, demand, authorization, direction, notice, consent, waiver or other action of the Holder of any Security shall bind every future Holder of the same Security and the Holder of every Security issued upon the registration of transfer thereof or in exchange therefor or in lieu thereof in respect of anything done, omitted or suffered to be done by the Trustee or the Partnership in reliance thereon, regardless of whether notation of such action is made upon such Security.

        Without limiting the foregoing, a Holder entitled hereunder to give or take any action hereunder with regard to any particular Security may do so with regard to all or any part of the principal amount of such Security or by one or more duly appointed agents each of which may do so pursuant to such appointment with regard to all or any different part of such principal amount.

        The Partnership may set any day as the record date for the purpose of determining the Holders of Outstanding Securities of any series entitled to give or take any request, demand, authorization, direction, notice, consent, waiver or other action provided or permitted by this Indenture to be given or taken by Holders of Securities of such series, but the Partnership shall have no obligation to do so. With regard to any record date set pursuant to this paragraph, the Holders of Outstanding Securities of the relevant series on such record date (or their duly appointed agents), and only such Persons, shall be entitled to give or take the relevant action, regardless of whether such Holders remain Holders after such record date.

SECTION 106. Notices, Etc., to Trustee and Partnership.

        Any request, demand, authorization, direction, notice, consent, waiver or Act of Holders or other document provided or permitted by this Indenture to be made upon, given or furnished to, or filed with,

SECTION 107. Notice to Holders; Waiver.

        Where this Indenture provides for notice to Holders of any event, such notice shall be sufficiently given (unless otherwise herein expressly provided) if in writing and mailed, first-class postage prepaid (if international

8


mail, by air mail), to each Holder affected by such event, at his address as it appears in the Security Register, not later than the latest date (if any), and not earlier than the earliest date (if any), prescribed for the giving of such notice. In any case where notice to Holders is given by mail, neither the failure to mail such notice, nor any defect in any notice so mailed, to any particular Holder shall affect the sufficiency of such notice with respect to other Holders. Any notice mailed to a Holder in the manner herein prescribed shall be conclusively deemed to have been received by such Holder, whether or not such Holder actually receives such notice.

        Where this Indenture provides for notice in any manner, such notice may be waived in writing by the Person entitled to receive such notice, either before or after the event, and such waiver shall be the equivalent of such notice. Waivers of notice by Holders shall be filed with the Trustee, but such filing shall not be a condition precedent to the validity of any action taken in reliance upon such waiver.

        In case by reason of the suspension of regular mail service or by reason of any other cause it shall be impracticable to give such notice by mail, then such notification as shall be made with the approval of the Trustee shall constitute a sufficient notification for every purpose hereunder.

SECTION 108. Conflict with Trust Indenture Act.

        If any provision hereof limits, qualifies or conflicts with a provision of the Trust Indenture Act that is required under such Act to be a part of and govern this Indenture, the latter provision shall control. If any provision of this Indenture modifies or excludes any provision of the Trust Indenture Act that may be so modified or excluded, the latter provision shall be deemed to apply to this Indenture as so modified or excluded, as the case may be.

SECTION 109. Effect of Headings and Table of Contents.

        The Article and Section headings herein and the Table of Contents are for convenience only and shall not affect the construction hereof.

SECTION 110. Successors and Assigns.

        All covenants and agreements in this Indenture by the Partnership shall bind its successors and assigns, whether so expressed or not.

SECTION 111. Separability Clause.

        In case any provision in this Indenture or in the Securities shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

SECTION 112. Benefits of Indenture.

        Nothing in this Indenture or in the Securities, express or implied, shall give to any Person, other than the parties hereto and their successors hereunder, the holders of Senior Debt and the Holders, any benefit or any legal or equitable right, remedy or claim under this Indenture.

SECTION 113. Governing Law.

        This Indenture and the Securities shall be governed by and construed in accordance with the laws of the State of New York.

SECTION 114. Legal Holidays.

        In any case where any Interest Payment Date, Redemption Date or Stated Maturity of any Security shall not be a Business Day at any Place of Payment, then (notwithstanding any other provision of this Indenture or of the Securities (other than a provision of the Securities of any series that specifically states that such provision shall apply in lieu of this Section 114)) payment of interest or principal (and any premium) need not be made at such Place of Payment on such date, but may be made on the next succeeding Business Day at such Place of

9


Payment with the same force and effect as if made on the Interest Payment Date or Redemption Date, or at the Stated Maturity, provided that no interest shall accrue for the period from and after such Interest Payment Date, Redemption Date or Stated Maturity, as the case may be.

SECTION 115. Securities in a Composite Currency, Currency Unit or Foreign Currency.

        Unless otherwise specified in an Officer's Certificate delivered pursuant to Section 301 of this Indenture with respect to a particular series of Securities, whenever for purposes of this Indenture any action may be taken by the Holders of a specified percentage in aggregate principal amount of Securities of all series or all series affected by a particular action at the time Outstanding and, at such time, there are Outstanding Securities of any series which are denominated in a coin, currency or currencies other than Dollars (including, but not limited to, any composite currency, currency units or Foreign Currency), then the principal amount of Securities of such series which shall be deemed to be Outstanding for the purpose of taking such action shall be that amount of Dollars that could be obtained for such amount at the Market Exchange Rate. For purposes of this Section 115, the term "Market Exchange Rate" shall mean the noon Dollar buying rate in The City of New York for cable transfers of such currency or currencies as published by the Federal Reserve Bank of New York, as of the most recent available date. If such Market Exchange Rate is not so available for any reason with respect to such currency, the Trustee shall use, in its sole discretion and without liability on its part, such quotation of the Federal Reserve Bank of New York as of the most recent available date, or quotations or rates of exchange from one or more major banks in The City of New York or in the country of issue of the currency in question, which for purposes of Euros shall be Brussels, Belgium, or such other quotations or rates of exchange as the Trustee shall deem appropriate. The provisions of this paragraph shall apply in determining the equivalent principal amount in respect of Securities of a series denominated in a currency other than Dollars in connection with any action taken by Holders of Securities pursuant to the terms of this Indenture.

        All decisions and determinations of the Trustee regarding the Market Exchange Rate or any alternative determination provided for in the preceding paragraph shall be in its sole discretion and shall, in the absence of manifest error, be conclusive to the extent permitted by law for all purposes and irrevocably binding upon the Issuer and all Holders.

SECTION 116. Judgment Currency.

        The Company agrees, to the fullest extent that it may effectively do so under applicable law, that (a) if for the purpose of obtaining judgment in any court it is necessary to convert the sum due in respect of the principal of or interest on the Securities of any series (the "Required Currency") into a currency in which a judgment will be rendered (the "Judgment Currency"), the rate of exchange used shall be the rate at which in accordance with normal banking procedures the Trustee could purchase in The City of New York the Required Currency with the Judgment Currency on the day on which final unappealable judgment is entered, unless such day is not a Banking Day, then, to the extent permitted by applicable law, the rate of exchange used shall be the rate at which in accordance with normal banking procedures the Trustee could purchase in The City of New York the Required Currency with the Judgment Currency on the Banking Day next preceding the day on which final unappealable judgment is entered and (b) its obligations under this Indenture to make payments in the Required Currency (i) shall not be discharged or satisfied by any tender, or any recovery pursuant to any judgment (whether or not entered in accordance with subsection (a)), in any currency other than the Required Currency, except to the extent that such tender or recovery shall result in the actual receipt, by the payee, of the full amount of the Required Currency expressed to be payable in respect of such payments, (ii) shall be enforceable as an alternative or additional cause of action for the purpose of recovering in the Required Currency the amount, if any, by which such actual receipt shall fall short of the full amount of the Required Currency so expressed to be payable and (iii) shall not be affected by judgment being obtained for any other sum due under this Indenture.

SECTION 117. Language of Notices, Etc.

        Any request, demand, authorization, direction, notice, consent, waiver or Act required or permitted under this Indenture shall be in the English language, ept that any published notice may be in an official language of the country of publication.

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SECTION 118. Non-Recourse to the General Partner; No Personal Liability of Officers, Directors, Employees or Partners.

        Obligations of the Partnership under this Indenture and the Securities hereunder are non-recourse to the General Partner, and its Affiliates (other than the Partnership), and payable only out of cash flow and assets of the Partnership. The Trustee, and each Holder of a Security by its acceptance thereof, will be deemed to have agreed in this Indenture that (1) neither the General Partner nor its assets (nor any of its Affiliates other than the Partnership, nor their respective assets) shall be liable for any of the obligations of the Partnership under this Indenture or such Securities, and (2) no director, officer, employee, stockholder or unitholder, as such, of the Partnership, the Trustee, the General Partners or any Affiliate of any of the foregoing entities shall have any personal liability in respect of the obligations of the Partnership under this Indenture or such Securities by reason of his, her or its status.

ARTICLE II
SECURITY FORMS

SECTION 201. Forms Generally.

        The Securities of each series shall be in substantially the form set forth in this Article II, or in such other form or forms as shall be established by or pursuant to a Board Resolution or in one or more indentures supplemental hereto, in each case with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by this Indenture, and may have such letters, numbers or other marks of identification and such legends or endorsements placed thereon as may be required to comply with the rules of any securities exchange or automated quotation system on which the Securities of such series may be listed or traded or Depositary therefor or as may, consistently herewith, be determined by the officers executing such Securities, as evidenced by their execution of the Securities. If the form of Securities of any series is established by action taken pursuant to a Board Resolution, a copy of an appropriate record of such action shall be certified by an authorized officer or other authorized Person on behalf of the Partnership and delivered to the Trustee at or prior to the delivery of the Partnership Order contemplated by Section 303 for the authentication and delivery of such Securities.

        The definitive Securities shall be printed, lithographed or engraved on steel engraved borders or may be produced in any other manner, all as determined by the officers executing such Securities, as evidenced by their execution of such Securities.

        The forms of Global Securities of any series shall have such provisions and legends as are customary for Securities of such series in global form, including without limitation any legend required by the Depositary for the Securities of such series.

SECTION 202. Form of Face of Security.

        [If the Security is an Original Issue Discount Security, insert-FOR PURPOSES OF SECTION 1275 OF THE UNITED STATES INTERNAL REVENUE CODE OF 1986, AS AMENDED, THE AMOUNT OF THE ORIGINAL ISSUE DISCOUNT IS. .. .. .. ., THE ISSUE DATE IS. .. .. ., 20.. . [AND] [,] THE YIELD TO MATURITY IS. .. .. .. . [,] [AND THE ORIGINAL ISSUE DISCOUNT FOR THE SHORT ACCRUAL PERIOD IS. .. .. .. . AND THE METHOD USED TO DETERMINE THE YIELD THEREFOR IS. .. ..]]

        [Insert any other legend required by the United States Internal Revenue Code and the regulations thereunder.]

        [If a Global Security, insert legend required by Section 204 of the Indenture.]

        [If applicable, insert — UNLESS THIS SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION, TO THE PARTNERSHIP OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY SECURITY ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE

11


DEPOSITORY TRUST COMPANY (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]

TC PIPELINES, LP
[TITLE OF SECURITY]

No.                           U.S. $                        

[CUSIP No. [                        ]]
 
 

        TC PIPELINES, LP, a Delaware limited partnership (herein called the "Partnership," which term includes any successor Person under the Indenture hereinafter referred to), for value received, hereby promises to pay to                        , or registered assigns, the principal sum of                        United States Dollars on                         [if the Security is to bear interest prior to Maturity, insert — , and to pay interest thereon from                        , or from the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually on                and                in each year, commencing                ,            , at the rate of    % per annum, until the principal hereof is paid or made available for payment [if applicable, insert — , and at the rate of    % per annum on any overdue principal and premium and on any overdue installment of interest]. [If applicable, insert — The amount of interest payable for any period shall be computed on the basis of twelve 30-day months and a 360-day year. The amount of interest payable for any partial period shall be computed on the basis of a 360-day year of twelve 30-day months and the days elapsed in any partial month. In the event that any date on which interest is payable on this Security is not a Business Day, then a payment of the interest payable on such date will be made on the next succeeding day which is a Business Day (and without any interest or other payment in respect of any such delay) with the same force and effect as if made on the date the payment was originally payable. A "Business Day" shall mean, when used with respect to any Place of Payment, each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in that Place of Payment are authorized or obligated by law, executive order or regulation to close.] The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in such Indenture, be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on the Regular Record Date for such interest, which shall be the                or                (whether or not a Business Day), as the case may be, next preceding such Interest Payment Date. Any such interest not so punctually paid or duly provided for shall forthwith cease to be payable to the Holder on such Regular Record Date and may either be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of Securities of this series not less than 10 days prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange or automated quotation system on which the Securities of this series may be listed or traded, and upon such notice as may be required by such exchange or automated quotation system, all as more fully provided in such Indenture].

        [If the Security is not to bear interest prior to Maturity, insert — The principal of this Security shall not bear interest except in the case of a default in payment of principal upon acceleration, upon redemption or at Stated Maturity and in such case the overdue principal of this Security shall bear interest at the rate of    % per annum (to the extent that the payment of such interest shall be legally enforceable), which shall accrue from the date of such default in payment to the date payment of such principal has been made or duly provided for. Interest on any overdue principal shall be payable on demand. Any such interest on any overdue principal that is not so paid on demand shall bear interest at the rate of    % per annum (to the extent that the payment of such interest shall be legally enforceable), which shall accrue from the date of such demand for payment to the date payment of such interest has been made or duly provided for, and such interest shall also be payable on demand.]

        [If a Global Security, insert — Payment of the principal of [(and premium, if any)] and [if applicable, insert — any such] interest on this Security will be made by transfer of immediately available funds to a bank

12


account in                        designated by the Holder in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts [state other currency].]

        [If a Definitive Security, insert — Payment of the principal of [(and premium, if any)] and [if applicable, insert — any such] interest on this Security will be made at the office or agency of the Partnership maintained for that purpose in                        , [in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts] [state other currency] [or subject to any laws or regulations applicable thereto and to the right of the Partnership (as provided in the Indenture) to rescind the designation of any such Paying Agent, at the [main] offices of                        in                         and                        in                         , or at such other offices or agencies as the Partnership may designate, by [United States Dollar] [state other currency] check drawn on, or transfer to a [United States Dollar] account maintained by the payee with, a bank in The City of New York (so long as the applicable Paying Agent has received proper transfer instructions in writing at least [    ] days prior to the payment date)] [if applicable, insert — ; provided, however, that payment of interest may be made at the option of the Partnership by [United States Dollar] [state other currency] check mailed to the addresses of the Persons entitled thereto as such addresses shall appear in the Security Register] [or by transfer to a [United States Dollar] [state other currency] account maintained by the payee with a bank in The City of New York [state other Place of Payment] (so long as the applicable Paying Agent has received proper transfer instructions in writing by the Record Date prior to the applicable Interest Payment Date)].]

        Reference is hereby made to the further provisions of this Security set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

        Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof by manual signature, this Security shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

        IN WITNESS WHEREOF, the Partnership has caused this instrument to be duly executed.

Dated:                        

    TC PIPELINES, LP,

 
 
By:
TC PipeLines GP, Inc.
Its General Partner

 
 
By:

 
 
Name:

 
 
Title:

SECTION 203. Form of Reverse of Security.

        This Security is one of a duly authorized issue of senior securities of the Partnership (herein called the "Securities"), issued and to be issued in one or more series under an Indenture dated as of [            ] [    ], [            ] (the "Indenture"), between the Partnership and [                        ], as Trustee (the "Trustee," which term includes any successor trustee under the Indenture), to which Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights, limitations of rights, obligations, duties and immunities thereunder of the Partnership, the Trustee and the Holders of the Securities and of the terms upon which the Securities are, and are to be, authenticated and delivered. As provided in the Indenture, the Securities may be issued in one or more series, which different series may be issued in various aggregate principal amounts, may mature at different times, may bear interest, if any, at different rates, may be subject to different

13


redemption provisions, if any, may be subject to different sinking, purchase or analogous funds, if any, may be subject to different covenants and Events of Default and may otherwise vary as in the Indenture provided or permitted. This Security is one of the series designated on the face hereof [if applicable, insert — , limited in aggregate principal amount to U.S.$            ].

        [If applicable, insert — The Securities of this series are subject to redemption upon not less than 30 nor more than 60 days' notice by mail, [if applicable, insert — (1) on                        in any year commencing with the year             and ending with the year            through operation of the sinking fund for this series at a Redemption Price equal to 100% of the principal amount, and (2)] at any time [if applicable, insert — on or after            ,            ], as a whole or in part, at the election of the Partnership, at the following Redemption Prices (expressed as percentages of the principal amount): If redeemed [if applicable, insert — on or before                        ,    %, and if redeemed] during the 12-month period beginning of the years indicated,

Year
   Redemption Price
   Year
   Redemption Price
             
             

and thereafter at a Redemption Price equal to    % of the principal amount, together in the case of any such redemption [if applicable, insert — (whether through operation of the sinking fund or otherwise)] with accrued interest to the Redemption Date, but interest installments whose Stated Maturity is on or prior to such Redemption Date will be payable to the Holders of such Securities, or one or more Predecessor Securities, of record at the close of business on the relevant Record Dates referred to on the face hereof, all as provided in the Indenture.]

        [If applicable, insert — The Securities of this series are subject to redemption upon not less than 30 nor more than 60 days' notice by mail, (1) on            in any year commencing with the year            and ending with the year            through operation of the sinking fund for this series at the Redemption Prices for redemption through operation of the sinking fund (expressed as percentages of the principal amount) set forth in the table below, and (2) at any time [if applicable, insert — on or after                        ], as a whole or in part, at the election of the Partnership, at the Redemption Prices for redemption otherwise than through operation of the sinking fund (expressed as percentages of the principal amount) set forth in the table below: If redeemed during the 12-month period beginning                        of the years indicated,

Year
   Redemption Price for Redemption Through Operation of the Sinking Fund
   Redemption Price for Redemption Otherwise than Through Operation of the Sinking Fund
         
         

and thereafter at a Redemption Price equal to    % of the principal amount, together in the case of any such redemption (whether through operation of the sinking fund or otherwise) with accrued interest to the Redemption Date, but interest installments whose Stated Maturity is on or prior to such Redemption Date will be payable to the Holders of such Securities, or one or more Predecessor Securities, of record at the close of business on the relevant Record Dates referred to on the face hereof, all as provided in the Indenture.]

        [If applicable, insert — The sinking fund for this series provides for the redemption in each year beginning with the year            and ending with the year            of [if applicable, — not less than $             ("mandatory sinking fund") and not more than] $            aggregate principal amount of Securities of this series. Securities of this series acquired or redeemed by the Partnership otherwise than through [if applicable, — mandatory] sinking fund payments may be credited against subsequent [if applicable, — mandatory] sinking fund payments otherwise required to be made [if applicable, — in the inverse order in which they become due].]

        [If the Security is subject to redemption in part of any kind, insert — In the event of redemption of this Security in part only, a new Security or Securities of this series and of like tenor for the unredeemed portion hereof will be issued in the name of the Holder hereof upon the cancellation hereof.]

        [If applicable, insert — The Securities of this series are not redeemable prior to Stated Maturity.]

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        [If the Security is not an Original Issue Discount Security, insert — If an Event of Default with respect to Securities of this series shall occur and be continuing, the principal of the Securities of this series may be declared due and payable in the manner and with the effect provided in the Indenture.]

        [If the Security is an Original Issue Discount Security, insert — If an Event of Default with respect to Securities of this series shall occur and be continuing, an amount of principal of the Securities of this series may be declared due and payable in the manner and with the effect provided in the Indenture. Such amount shall be equal to — insert formula for determining the amount. Upon payment (1) of the amount of principal so declared due and payable, and (2) of interest on any overdue principal and overdue interest (in each case to the extent that the payment of such interest shall be legally enforceable), all of the Partnership's obligations in respect of the payment of the principal of and interest, if any, on the Securities of this series shall terminate.]

        The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Partnership and the rights of the Holders of the Securities of each series to be affected under the Indenture at any time by the Partnership and the Trustee with the consent of the Holders of a majority in principal amount of the Securities at the time Outstanding of all series to be affected (voting as one class). The Indenture also contains provisions permitting the Holders of specified percentages in principal amount of the Securities of each series at the time Outstanding, on behalf of the Holders of all Securities of such series, to waive compliance by the Partnership with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Security shall be conclusive and binding upon such Holder and upon all future Holders of this Security and of any Security issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, regardless of whether notation of such consent or waiver is made upon this Security.

        As provided in and subject to the provisions of the Indenture, the Holder of this Security shall not have the right to institute any proceeding with respect to the Indenture or for the appointment of a receiver or trustee or for any other remedy thereunder, unless such Holder shall have previously given the Trustee written notice of a continuing Event of Default with respect to the Securities of this series, the Holders of not less than 25% in principal amount of the Securities of this series at the time Outstanding shall have made written request to the Trustee to institute proceedings in respect of such Event of Default as Trustee and offered the Trustee reasonable indemnity and the Trustee shall not have received from the Holders of a majority in principal amount of Securities of this series at the time Outstanding a direction inconsistent with such request, and shall have failed to institute any such proceeding, for 60 days after receipt of such notice, request and offer of indemnity. The foregoing shall not apply to any suit instituted by the Holder of this Security for the enforcement of any payment of principal hereof or [any premium or] interest hereon on or after the respective due dates expressed herein.

        No reference herein to the Indenture and no provision of this Security or of the Indenture shall alter or impair the obligation of the Partnership, which is absolute and unconditional, to pay the principal of and [any premium and] interest on this Security at the times, place(s) and rate, and in the coin or currency, herein prescribed.

        [If a Global Security, insert — This Global Security or portion hereof may not be exchanged for Definitive Securities of this series except in the limited circumstances provided in the Indenture.

        The holders of beneficial interests in this Global Security will not be entitled to receive physical delivery of Definitive Securities except as described in the Indenture and will not be considered the Holders thereof for any purpose under the Indenture.]

        [If a Definitive Security, insert — As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Security is registerable in the Security Register, upon surrender of this Security for registration of transfer at the office or agency of the Partnership in [if applicable, insert — any place where the principal of and any premium and interest on this Security are payable] [if applicable, insert — The City of New York [, or, subject to any laws or regulations applicable thereto and to the right of the Partnership (limited as provided in the Indenture) to rescind the designation of any such transfer agent, at the [main] offices of                        in                         and                         in                         or at such other offices or agencies as the Partnership may designate]], duly endorsed by, or accompanied by a written instrument of transfer in form

15


satisfactory to the Partnership and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Securities of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees.]

        The Securities of this series are issuable only in registered form without coupons in denominations of U.S.$ [state other currency] and any integral multiple thereof. As provided in the Indenture and subject to certain limitations therein set forth, Securities of this series are exchangeable for a like aggregate principal amount of Securities of this series and of like tenor of a different authorized denomination, as requested by the Holder surrendering the same.

        No service charge shall be made for any such registration of transfer or exchange, but the Partnership may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

        Prior to due presentment of this Security for registration of transfer, the Partnership, the Trustee and any agent of the Partnership or the Trustee may treat the Person in whose name this Security is registered as the owner hereof for all purposes, regardless of whether this Security is overdue, and neither the Partnership, the Trustee nor any such agent shall be affected by notice to the contrary.

        This Security is subordinated in right of payment to Senior Debt, to the extent provided in the Indenture.

        Obligations of the Partnership under the Indenture and the Securities thereunder, including this Security, are non-recourse to TC PipeLines GP, Inc. (the "General Partner") and its Affiliates (other than the Partnership), and payable only out of cash flow and assets of the Partnership. The Trustee, and each Holder of a Security by its acceptance hereof, will be deemed to have agreed in the Indenture that (1) neither the General Partner nor its assets (nor any of its Affiliates other than the Partnership, nor their respective assets) shall be liable for any of the obligations of the Partnership under the Indenture or such Securities, including this Security, and (2) no director, officer, employee, stockholder or unitholder, as such, of the Partnership, the Trustee, the General Partner or any Affiliate of any of the foregoing entities shall have any personal liability in respect of the obligations of the Partnership under the Indenture or such Securities by reason of his, her or its status.

        The Indenture provides that the Partnership (a) will be discharged from any and all obligations in respect of the Securities (except for certain obligations described in the Indenture), or (b) need not comply with certain restrictive covenants of the Indenture, in each case if the Partnership deposits, in trust, with the Trustee money or U.S. Government Obligations (or a combination thereof) which through the payment of interest thereon and principal thereof in accordance with their terms will provide money, in an amount sufficient to pay all the principal of and interest on the Securities, but such money need not be segregated from other funds except to the extent required by law.

        This Security shall be governed by and construed in accordance with the laws of the State of New York.

        All terms used in this Security which are defined in the Indenture shall have the meanings assigned to them in the Indenture.

        [If a Definitive Security, insert as a separate page —

        FOR VALUE RECEIVED, the undersigned hereby sell(s), assign(s) and transfer(s) unto                       
(Please Print or Typewrite Name and Address of Assignee) the within instrument of TC PIPELINES, LP and does hereby irrevocably constitute and appoint                        Attorney to transfer said instrument on the books of the within-named Partnership, with full power of substitution in the premises.

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        Please Insert Social Security or Other Identifying Number of Assignee:


 
 
 
Dated:   (Signature):

Signature
 
Guarantee:

(Participant in a Recognized Signature Guaranty Medallion Program)

        NOTICE: The signature to this assignment must correspond with the name as written upon the face of the within instrument in every particular, without alteration or enlargement or any change whatever.]

SECTION 204. Global Securities.

        Every Global Security authenticated and delivered hereunder shall bear a legend in substantially the following form:

        If Securities of a series are issuable in whole or in part in the form of one or more Global Securities, as specified as contemplated by Section 301, then, notwithstanding clause (9) of Section 301 and the provisions of Section 302, any Global Security shall represent such of the Outstanding Securities of such series as shall be specified therein and may provide that it shall represent the aggregate amount of Outstanding Securities from time to time endorsed thereon and that the aggregate amount of Outstanding Securities represented thereby may from time to time be reduced or increased, as the case may be, to reflect exchanges. Any endorsement of a Global Security to reflect the amount, or any reduction or increase in the amount, of Outstanding Securities represented thereby shall be made in such manner and upon instructions given by such Person or Persons as shall be specified therein or in a Partnership Order. Subject to the provisions of Sections 303, 304 and 305, the Trustee shall deliver and redeliver any Global Security in the manner and upon instructions given by the Person or Persons specified therein or in the applicable Partnership Order. Any instructions by the Partnership with respect to endorsement or delivery or redelivery of a Global Security shall be in a Partnership Order (which need not comply with Section 102 and need not be accompanied by an Opinion of Counsel).

        The provisions of the last sentence of Section 303 shall apply to any Security represented by a Global Security if such Security was never issued and sold by the Partnership and the Partnership delivers to the Trustee the Global Security together with a Partnership Order (which need not comply with Section 102 and need not be accompanied by an Opinion of Counsel) with regard to the reduction or increase, as the case may be, in the principal amount of Securities represented thereby, together with the written statement contemplated by the last sentence of Section 303.

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SECTION 205. Form of Trustee's Certificate of Authentication.

        The Trustee's certificate of authentication shall be in substantially the following form:

        This is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.


 
 
 
As Trustee

 
 
By:
Authorized Officer

ARTICLE III
THE SECURITIES

SECTION 301.    Amount Unlimited; Issuable in Series.

        The aggregate principal amount of Securities which may be authenticated and delivered under this Indenture is unlimited.

        The Securities may be issued in one or more series. There shall be established in or pursuant to a Board Resolution and set forth, or determined in the manner provided, in an Officers' Certificate, or established in one or more indentures supplemental hereto, prior to the issuance of Securities of any series,

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        All Securities of any one series shall be substantially identical except as to denomination and except as may otherwise be provided in or pursuant to the Board Resolution referred to above and (subject to Section 303) set forth, or determined in the manner provided, in the Officers' Certificate referred to above or in any such indenture supplemental hereto.

        All Securities of any one series need not be issued at the same time and, unless otherwise provided, a series may be reopened, without the consent of the Holders, for increases in the aggregate principal amount of such series of Securities and issuances of additional Securities of such series or for the establishment of additional terms with respect to the Securities of such series.

        If any of the terms of the series are established by action taken by or pursuant to a Board Resolution, a copy of an appropriate record of such action shall be certified by an authorized officer or other authorized person of the General Partner on behalf of the Partnership and delivered to the Trustee at or prior to the delivery of the Officers' Certificate setting forth, or providing the manner for determining, the terms of the series.

        With respect to Securities of a series subject to a Periodic Offering, such Board Resolution or Officers' Certificate may provide general terms for Securities of such series and provide either that the specific terms of particular Securities of such series shall be specified in a Partnership Order, or that such terms shall be determined by the Partnership, or one or more of the Partnership's agents designated in an Officers' Certificate, in accordance with a Partnership Order.

SECTION 302.    Denominations.

        The Securities of each series shall be issuable only in registered form without coupons in such denominations as shall be specified as contemplated by Section 301. In the absence of any such specified denomination with respect to the Securities of any series, the Securities of such series shall be issuable in denominations of $1,000 and any integral multiple thereof.

SECTION 303.    Execution, Authentication, Delivery and Dating.

        The Securities shall be executed on behalf of the Partnership by the Chief Executive Officer, Chief Financial Officer, President or any Vice President of the General Partner and need not be attested. The signature of any of these officers on the Securities may be manual or facsimile.

        Securities bearing the manual or facsimile signatures of individuals who were at any time the proper officers of the General Partner shall bind the Partnership, notwithstanding that such individuals or any of them have ceased to hold such offices prior to the authentication and delivery of such Securities or did not hold such offices at the date of such Securities.

        At any time and from time to time after the execution and delivery of this Indenture, the Partnership may deliver Securities of any series executed by the Partnership to the Trustee for authentication, together with a Partnership Order for the authentication and delivery of such Securities, and the Trustee in accordance with the Partnership Order shall authenticate and deliver such Securities; provided, however, that in the case of Securities offered in a Periodic Offering, the Trustee shall authenticate and deliver such Securities from time to time in accordance with such other procedures (including, without limitation, the receipt by the Trustee of oral or electronic instructions from the Partnership or its duly authorized agents, thereafter promptly confirmed in writing) acceptable to the Trustee as may be specified by or pursuant to a Partnership Order delivered to the Trustee prior to the time of the first authentication of Securities of such series. If the form or terms of the Securities of the series have been established in or pursuant to one or more Board Resolutions as permitted by Sections 201 and 301, in authenticating such Securities, and accepting the additional responsibilities under this Indenture in relation to such Securities, the Trustee shall be entitled to receive such documents as it may

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reasonably request. The Trustee shall also be entitled to receive, and (subject to Section 601) shall be fully protected in relying upon, an Opinion of Counsel stating,

        If such form or forms or terms have been so established, the Trustee shall not be required to authenticate such Securities if the issue of such Securities pursuant to this Indenture will affect the Trustee's own rights, duties or immunities under the Securities and this Indenture or otherwise in a manner which is not reasonably acceptable to the Trustee.

        Notwithstanding the provisions of Section 301 and of the preceding paragraph, if all Securities of a series are not to be originally issued at one time, it shall not be necessary to deliver the Officers' Certificate otherwise required pursuant to Section 301 or the Partnership Order and Opinion of Counsel otherwise required pursuant to such preceding paragraph at or prior to the time of authentication of each Security of such series if such documents are delivered at or prior to the authentication upon original issuance of the first Security of such series to be issued.

        With respect to Securities of a series offered in a Periodic Offering, the Trustee may rely, as to the authorization by the Partnership of any of such Securities, the form or forms and terms thereof and the legality, validity, binding effect and enforceability thereof, upon the Opinion of Counsel and the other documents delivered pursuant to Sections 201 and 301 and this Section 303, as applicable, in connection with the first authentication of Securities of such series.

        Each Security shall be dated the date of its authentication.

        No Security shall be entitled to any benefit under this Indenture or be valid or obligatory for any purpose unless there appears on such Security a certificate of authentication substantially in the form provided for herein executed by the Trustee by manual signature of an authorized officer, and such certificate upon any Security shall be conclusive evidence, and the only evidence, that such Security has been duly authenticated and delivered hereunder and is entitled to the benefits of this Indenture.

        Notwithstanding the foregoing, if any Security shall have been authenticated and delivered hereunder but never issued and sold by the Partnership, and the Partnership shall deliver such Security to the Trustee for

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cancellation as provided in Section 309 for all purposes of this Indenture, such Security shall be deemed never to have been authenticated and delivered hereunder and shall never be entitled to the benefits of this Indenture.

SECTION 304.    Temporary Securities.

        Pending the preparation of Definitive Securities of any series, the Partnership may execute, and upon Partnership Order the Trustee shall authenticate and deliver, temporary Securities which are printed, lithographed, typewritten, mimeographed or otherwise produced, in any authorized denomination, substantially of the tenor of the Definitive Securities in lieu of which they are issued and with such appropriate insertions, omissions, substitutions and other variations as the officers executing such Securities may determine, as evidenced by their execution of such Securities.

        If temporary Securities of any series are issued, the Partnership will cause Definitive Securities of that series to be prepared without unreasonable delay. After the preparation of Definitive Securities of such series, the temporary Securities of such series shall be exchangeable for Definitive Securities of such series upon surrender of the temporary Securities of such series at the office or agency of the Partnership maintained pursuant to Section 1002 for the purpose of exchanges of Securities of such series, without charge to the Holder. Upon surrender for cancellation of any one or more temporary Securities of any series the Partnership shall execute and the Trustee shall authenticate and deliver in exchange therefor Definitive Securities of the same series and tenor, of any authorized denominations and of a like aggregate principal amount. Until so exchanged the temporary Securities of any series shall in all respects be entitled to the same benefits under this Indenture as Definitive Securities of such series and tenor.

SECTION 305.    Registration, Registration of Transfer and Exchange.

        The Partnership shall cause to be kept at the office or agency of the Partnership in  [                        ] (or in any other office or agency of the Partnership in a Place of Payment required by Section 1002) a register (the register maintained in such office being herein sometimes referred to as the "Security Register") in which, subject to such reasonable regulations as it may prescribe, the Partnership shall provide for the registration of Securities and of transfers of Securities. The Trustee is hereby appointed as the initial "Security Registrar" for the purpose of registering Securities and transfers of Securities as herein provided and its corporate trust office which, at the date hereof, is located at [                        ], as the initial office or agency in  [                        ] where the Security Register will be maintained. The Partnership may at any time replace such Security Registrar, change such office or agency or act as its own Security Registrar. The Partnership will give prompt written notice to the Trustee of any change of the Security Registrar or of the location of such office or agency.

        Upon surrender for registration of transfer of any Security of any series at the office or agency of the Partnership maintained pursuant to Section 1002 for such purpose, the Partnership shall execute, and the Trustee shall authenticate and deliver, in the name of the designated transferee or transferees, one or more new Securities of the same series and tenor, of any authorized denominations and of a like aggregate principal amount.

        At the option of the Holder, Securities of any series (except a Global Security) may be exchanged for other Securities of the same series and tenor, of any authorized denominations and of a like aggregate principal amount, upon surrender of the Securities to be exchanged at such office or agency. Whenever any Securities are so surrendered for exchange, the Partnership shall execute, and the Trustee shall authenticate and deliver, the Securities which the Holder making the exchange is entitled to receive.

        All Securities issued upon any registration of transfer or exchange of Securities shall be the valid obligations of the Partnership, evidencing the same debt, and entitled to the same benefits under this Indenture, as the Securities surrendered upon such registration of transfer or exchange.

        Every Security presented or surrendered for registration of transfer or for exchange shall (if so required by the Partnership or the Trustee) be duly endorsed, or be accompanied by a written instrument of transfer in form satisfactory to the Partnership and the Security Registrar duly executed, by the Holder thereof or his attorney duly authorized in writing.

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        No service charge shall be imposed for any registration of transfer or exchange of Securities, but the Partnership may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in connection with any registration of transfer or exchange of Securities, other than exchanges pursuant to Section 304, 906 or 1107 not involving any transfer.

        Neither the Trustee nor the Partnership shall be required (1) to issue, register the transfer of or exchange Securities of any series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of Securities of that series selected for redemption under Section 1103 and ending at the close of business on the day of such mailing, or (2) to register the transfer of or exchange any Security so selected for redemption in whole or in part, except the unredeemed portion of any Security being redeemed in part.

        Notwithstanding any other provisions of this Indenture and except as otherwise specified with respect to any particular series of Securities as contemplated by Section 301, a Global Security representing all or a portion of the Securities of a series may not be transferred, except as a whole by the Depositary for such series to a nominee of such Depositary or by a nominee of such Depositary to such Depositary or another nominee of such Depositary or by such Depositary or any such nominee to a successor Depositary for such series or a nominee of such successor Depositary. Every Security authenticated and delivered upon registration or transfer of or in exchange for or in lieu of, a Global Security shall be a Global Security except as provided in the two paragraphs immediately following.

        If at any time the Depositary for any Securities of a series represented by one or more Global Securities notifies the Partnership that it is unwilling or unable to continue as Depositary for such Securities or if at any time the Depositary for such Securities shall no longer be eligible to continue as Depositary under Section 101 or ceases to be a clearing agency registered under the Exchange Act, the Partnership shall appoint a successor Depositary with respect to such Securities. If a successor Depositary for such Securities is not appointed by the Partnership within 90 days after the Partnership receives such notice or becomes aware of such ineligibility, the Partnership's election pursuant to Section 301 that such Securities be represented by one or more Global Securities shall no longer be effective and the Partnership will execute, and the Trustee, upon receipt of a Partnership Order for the authentication and delivery of Definitive Securities of such series, will authenticate and deliver, Securities of such series in definitive registered form without coupons, in any authorized denominations, in an aggregate principal amount equal to the principal amount of the Global Security or Securities representing such Securities in exchange for such Global Security or Securities registered in the names of such Persons as the Depository shall direct.

        The Partnership may at any time and in its sole discretion determine that the Securities of any series issued in the form of one or more Global Securities shall no longer be represented by a Global Security or Securities. In such event the Partnership will execute, and the Trustee, upon receipt of a Partnership Order for the authentication and delivery of the Definitive Securities of such series, will authenticate and deliver, Securities of such series in definitive registered form without coupons, in any authorized denominations, in an aggregate principal amount equal to the principal amount of the Global Security or Securities representing such Securities in exchange for such Global Security or Securities registered in the names of such Persons as the Depository shall direct.

        If specified by the Partnership pursuant to Section 301 with respect to Securities represented by a Global Security, the Depositary for such Global Security may surrender such Global Security in exchange in whole or in part for Securities of the same series and tenor in definitive registered form on such terms as are acceptable to the Partnership and such Depositary. Thereupon, the Partnership shall execute, and the Trustee, upon receipt of a Partnership Order for the authentication and delivery of Securities in definitive registered form, shall authenticate and deliver, without service charge,

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SECTION 306.    Mutilated, Destroyed, Lost and Stolen Securities.

        If any mutilated Security is surrendered to the Trustee, together with such security or indemnity as may be required by the Partnership or the Trustee to save each of them and any agent of either of them harmless, the Partnership shall execute and the Trustee shall authenticate and deliver in exchange therefor a new Security of the same series and of like tenor and principal amount and bearing a number not contemporaneously Outstanding.

        If there shall be delivered to the Partnership and the Trustee (1) evidence to their satisfaction of the destruction, loss or theft of any Security and (2) such security or indemnity as may be required by them to save each of them and any agent of either of them harmless, then, in the absence of notice to the Partnership or the Trustee that such Security has been acquired by a bona fide purchaser, the Partnership shall execute and the Trustee shall authenticate and deliver, in lieu of any such destroyed, lost or stolen Security, a new Security of the same series and of like tenor and principal amount and bearing a number not contemporaneously Outstanding.

        In case any such mutilated, destroyed, lost or stolen Security has become or is about to become due and payable, the Partnership in its discretion may, instead of issuing a new Security, pay such Security.

        Upon the issuance of any new Security under this Section 306, the Partnership may require the payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in relation thereto and any other expenses (including the fees and expenses of the Trustee) connected therewith. Every new Security of any series issued pursuant to this Section 306 in lieu of any destroyed, lost or stolen Security shall constitute an original additional contractual obligation of the Partnership, whether or not the mutilated, destroyed, lost or stolen Security shall be at any time enforceable by anyone, and shall be entitled to all the benefits of this Indenture equally and proportionately with any and all other Securities of that series duly issued hereunder.

        The provisions of this Section 306 are exclusive and shall preclude (to the extent lawful) all other rights and remedies with respect to the replacement or payment of mutilated, destroyed, lost or stolen Securities.

SECTION 307.    Payment of Interest; Interest Rights Preserved.

        Except as otherwise provided as contemplated by Section 301 with respect to any series of Securities, interest on any Security which is payable, and is punctually paid or duly provided for, on any Interest Payment Date shall be paid to the Person in whose name that Security (or one or more Predecessor Securities) is registered at the close of business on the Regular Record Date for such interest.

        Any interest on any Security of any series which is payable, but is not punctually paid or duly provided for, on any Interest Payment Date (herein called "Defaulted Interest") shall forthwith cease to be payable to the

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Holder on the relevant Regular Record Date by virtue of having been such Holder, and such Defaulted Interest may be paid by the Partnership, at its election in each case, as provided in clause (1) or (2) below:

        Subject to the foregoing provisions of this Section 307 and Section 305, each Security delivered under this Indenture upon registration of transfer of or in exchange for or in lieu of any other Security, shall carry the rights to interest accrued and unpaid, and to accrue, which were carried by such other Security.

SECTION 308.    Persons Deemed Owners.

        Except as otherwise provided as contemplated by Section 301 with respect to any series of Securities, prior to due presentment of a Security for registration of transfer, the Partnership, the Trustee and any agent of the Partnership or the Trustee may treat the Person in whose name such Security is registered as the owner of such Security for the purpose of receiving payment of principal of and any premium and (subject to Sections 305 and 307) any interest on such Security and for all other purposes whatsoever, whether or not such Security is overdue, and neither the Partnership, the Trustee nor any agent of the Partnership or the Trustee shall be affected by notice to the contrary.

        No holder of any beneficial interest in any Global Security held on its behalf by a Depositary shall have any rights under this Indenture with respect to such Global Security, and such Depositary may be treated by the Partnership, the Trustee and any agent of the Partnership or the Trustee as the owner of such Global Security for all purposes whatsoever. None of the Partnership, the Trustee nor any agent of the Partnership or the Trustee will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests of a Global Security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

SECTION 309.    Cancellation.

        All Securities surrendered for payment, redemption, registration of transfer or exchange or for credit against any sinking fund payment shall, if surrendered to any Person other than the Trustee, be delivered to the Trustee and shall be promptly canceled by it. The Partnership may at any time deliver to the Trustee for

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cancellation any Securities previously authenticated and delivered hereunder which the Partnership may have acquired in any manner whatsoever, and may deliver to the Trustee (or to any other Person for delivery to the Trustee) for cancellation any Securities previously authenticated hereunder which the Partnership has not issued and sold, and all Securities so delivered shall be promptly canceled by the Trustee. No Securities shall be authenticated in lieu of or in exchange for any Securities canceled as provided in this Section 309, except as expressly permitted by this Indenture. All canceled Securities held by the Trustee shall be disposed of in accordance with its customary practices, and the Trustee shall thereafter deliver to the Partnership a certificate with respect to such disposition.

SECTION 310.    Computation of Interest.

        Except as otherwise specified as contemplated by Section 301 for Securities of any series, interest on the Securities of each series shall be computed on the basis of a 360-day year of twelve 30-day months and interest on the Securities of each series for any partial period shall be computed on the basis of a 360-day year of twelve 30-day months and the number of days elapsed in any partial month.

SECTION 311.    CUSIP Numbers.

        The Partnership in issuing the Securities may use "CUSIP" numbers (if then generally in use, and in addition to the other identification numbers printed on the Securities), and, if so, the Trustee shall use "CUSIP" numbers in notices of redemption as a convenience to Holders; provided, however, that any such notice may state that no representation is made as to the correctness of such "CUSIP" numbers either as printed on the Securities or as contained in any notice of a redemption and that reliance may be placed only on the other identification numbers printed on the Securities, and any such redemption shall not be affected by any defect in or omission of such "CUSIP" numbers.

ARTICLE IV
SATISFACTION AND DISCHARGE

SECTION 401. Satisfaction and Discharge of Indenture.

        This Indenture shall upon Partnership Request cease to be of further effect with respect to Securities of any series (except as to any surviving rights of registration of transfer or exchange of such Securities herein expressly provided for), and the Trustee, at the expense of the Partnership, shall execute proper instruments acknowledging satisfaction and discharge of this Indenture with respect to such Securities, when

and the Partnership in the case of (i), (ii) or (iii) above, has irrevocably deposited or caused to be deposited with the Trustee as trust funds in trust for this purpose an amount of money in the currency or currency units in which such Securities are payable sufficient to pay and discharge the entire indebtedness on such Securities not theretofore delivered to the Trustee for cancellation, for principal and any premium and interest to the date of such deposit (in the case of Securities which have become due and payable) or to the Stated Maturity or Redemption Date, as the case may be;

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        Notwithstanding the satisfaction and discharge of this Indenture with respect to Securities of any series, (x) the obligations of the Partnership to the Trustee under Section 607, the obligations of the Trustee to any Authenticating Agent under Section 614 and the right of the Trustee to resign under Section 610 shall survive, and (y) if money shall have been deposited with the Trustee pursuant to subclause (b) of clause (1) of this Section 401, the obligations of the Partnership and/or the Trustee under Sections 402, 606, 701 and 1002 and the last paragraph of Section 1003 shall survive.

SECTION 402. Application of Trust Money.

        Subject to the provisions of the last paragraph of Section 1003, all money deposited with the Trustee pursuant to Section 401 shall be held in trust and applied by it, in accordance with the provisions of the Securities and this Indenture, to the payment, either directly or through any Paying Agent (including the Partnership acting as its own Paying Agent) as the Trustee may determine, to the Persons entitled thereto, of the principal and any premium and interest for whose payment such money has been deposited with the Trustee.

ARTICLE V
REMEDIES

SECTION 501. Events of Default.

        "Event of Default," wherever used herein with respect to Securities of any series, means any one of the following events (whatever the reason for such Event of Default and whether it shall be voluntary or involuntary or be effected by operation of law or pursuant to any judgment, decree or order of any court or any order, rule or regulation of any administrative or governmental body):

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SECTION 502. Acceleration of Maturity; Rescission and Annulment.

        If an Event of Default with respect to Securities of any series at the time Outstanding occurs and is continuing, then in every such case the Trustee or the Holders of not less than 25% in principal amount of the Outstanding Securities of that series may declare the principal amount of (or, if any of the Securities of that series are Original Issue Discount Securities, such portion of the principal amount of such Securities as may be specified in the terms thereof), and accrued but unpaid interest, if any, on all of the Securities of that series to be due and payable immediately, by a notice in writing to the Partnership (and to the Trustee if given by Holders), and upon any such declaration such principal amount (or specified amount) shall become immediately due and payable. Notwithstanding the foregoing, if an Event of Default specified in clause (4) or (5) of Section 501 occurs, the Securities of any series at the time Outstanding shall be due and payable immediately without further action or notice.

        At any time after such a declaration of acceleration with respect to Securities of any series has been made and before a judgment or decree for payment of the money due has been obtained by the Trustee as hereinafter in this Article provided, the Holders of a majority in principal amount of the Outstanding Securities of that series, by written notice to the Partnership and the Trustee, may rescind and annul such declaration and its consequences if

        No such rescission shall affect any subsequent Default or impair any right consequent thereon.

SECTION 503. Collection of Indebtedness and Suits for Enforcement by Trustee.

        The Partnership covenants that if

the Partnership will, upon demand of the Trustee, pay to it, for the benefit of the Holders of such Securities, the whole amount then due and payable on such Securities for principal and any premium and interest and, to the extent that payment of such interest shall be legally enforceable, interest on any overdue principal and premium and on any overdue interest, at the rate or rates prescribed therefor in such Securities, and, in addition thereto, such further amount as shall be sufficient to cover the costs and expenses of collection, including the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel.

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        If the Partnership fails to pay such amounts forthwith upon such demand, the Trustee, in its own name and as trustee of an express trust, may institute a judicial proceeding for the collection of the sums so due and unpaid, may prosecute such proceeding to judgment or final decree and may enforce the same against the Partnership or any other obligor upon such Securities and collect the moneys adjudged or decreed to be payable in the manner provided by law out of the property of the Partnership or any other obligor upon such Securities, wherever situated.

        Subject to Article XIV, if an Event of Default with respect to Securities of any series occurs and is continuing, the Trustee may in its discretion proceed to protect and enforce its rights and the rights of the Holders of Securities of such series by such appropriate judicial proceedings as the Trustee shall deem most effectual to protect and enforce any such rights, whether for the specific enforcement of any covenant or agreement in this Indenture or in aid of the exercise of any power granted herein, or to enforce any other proper remedy.

SECTION 504. Trustee May File Proofs of Claim.

        In case of the pendency of any receivership, insolvency, liquidation, bankruptcy, reorganization, arrangement, adjustment, composition or other judicial proceeding relative to the Partnership or any other obligor upon the Securities, their property or their creditors, the Trustee (irrespective of whether the principal of the Securities shall then be due and payable as therein expressed or by declaration or otherwise and irrespective of whether the Trustee shall have made any demand on the Partnership for the payment of overdue principal or interest) shall be entitled and empowered, by intervention in such proceeding or otherwise,

and any custodian, receiver, assignee, trustee, liquidator, sequestrator or other similar official in any such judicial proceeding is hereby authorized by each Holder to make such payments to the Trustee and, in the event that the Trustee shall consent to the making of such payments directly to the Holders, to pay to the Trustee any amount due it for the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel, and any other amounts due the Trustee under Section 607.

        No provision of this Indenture shall be deemed to authorize the Trustee to authorize or consent to or accept or adopt on behalf of any Holder any plan of reorganization, arrangement, adjustment or composition affecting the Securities or the rights of any Holder thereof or to authorize the Trustee to vote in respect of the claim of any Holder in any such proceeding; provided, however, that the Trustee may, on behalf of the Holders, vote for the election of a trustee in bankruptcy or similar official and be a member of a creditors' or other similar committee.

SECTION 505. Trustee May Enforce Claims Without Possession of Securities.

        All rights of action and claims under this Indenture or the Securities may be prosecuted and enforced by the Trustee without the possession of any of the Securities or the production thereof in any proceeding relating thereto, and any such proceeding instituted by the Trustee shall be brought in its own name as trustee of an express trust, and any recovery of judgment shall, after provision for the payment of the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel, be for the ratable benefit of the Holders of the Securities in respect of which such judgment has been recovered.

SECTION 506. Application of Money Collected.

        Any money collected by the Trustee pursuant to this Article shall be applied in the following order, at the date or dates fixed by the Trustee and, in case of the distribution of such money on account of principal or any

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premium or interest, upon presentation of the Securities and the notation thereon of the payment if only partially paid and upon surrender thereof if fully paid:

FIRST:   To the payment of all amounts due the Trustee under Section 607;

SECOND:
 
Subject to Article XIV, to the payment of the amounts then due and unpaid for principal of and any premium and interest on the Securities in respect of which or for the benefit of which such money has been collected, ratably, without preference or priority of any kind, according to the amounts due and payable on such Securities for principal and any premium and interest, respectively; and

THIRD:
 
The balance, if any, to the Partnership.

SECTION 507. Limitation on Suits.

        No Holder of any Security of any series shall have any right to institute any proceeding, judicial or otherwise, with respect to this Indenture, or for the appointment of a receiver or trustee, or for any other remedy hereunder, unless

it being understood and intended that no one or more of such Holders shall have any right in any manner whatever by virtue of, or by availing of, any provision of this Indenture to affect, disturb or prejudice the rights of any other of such Holders, or to obtain or to seek to obtain priority or preference over any other of such Holders or to enforce any right under this Indenture, except in the manner herein provided and for the equal and ratable benefit of all such Holders.

SECTION 508. Unconditional Right of Holders to Receive Principal, Premium and Interest.

        Notwithstanding any other provision in this Indenture, the Holder of any Security shall have the right, which is absolute and unconditional, to receive payment of the principal of and any premium and (subject to Sections 305 and 307) interest on such Security on the respective Stated Maturity or Maturities expressed in such Security (or, in the case of redemption, on the Redemption Date) and to institute suit for the enforcement of any such payment, and such rights shall not be impaired without the consent of such Holder.

SECTION 509. Restoration of Rights and Remedies.

        If the Trustee or any Holder has instituted any proceeding to enforce any right or remedy under this Indenture and such proceeding has been discontinued or abandoned for any reason, or has been determined adversely to the Trustee or to such Holder, then and in every such case, subject to any determination in such proceeding, the Partnership, the Trustee and the Holders shall be restored severally and respectively to their former positions hereunder, and thereafter all rights and remedies of the Trustee and the Holders shall continue as though no such proceeding had been instituted.

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SECTION 510. Rights and Remedies Cumulative.

        Except as otherwise provided with respect to the replacement or payment of mutilated, destroyed, lost or stolen Securities in the last paragraph of Section 306, no right or remedy herein conferred upon or reserved to the Trustee or to the Holders is intended to be exclusive of any other right or remedy, and every right and remedy shall, to the extent permitted by law, be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in equity or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent the concurrent assertion or employment of any other appropriate right or remedy.

SECTION 511. Delay or Omission Not Waiver.

        No delay or omission of the Trustee or of any Holder of any Securities to exercise any right or remedy accruing upon any Event of Default shall impair any such right or remedy or constitute a waiver of any such Event of Default or an acquiescence therein. Every right and remedy given by this Article or by law to the Trustee or to the Holders may be exercised from time to time, and as often as may be deemed expedient, by the Trustee or by the Holders, as the case may be.

SECTION 512. Control by Holders.

        The Holders of a majority in aggregate principal amount of the Outstanding Securities of any series shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred on the Trustee, with respect to the Securities of such series; provided, however, that

SECTION 513. Waiver of Past Defaults.

        The Holders of not less than a majority in principal amount of the Outstanding Securities of any series may on behalf of the Holders of all the Securities of such series waive any past default hereunder with respect to such series and its consequences, except:

        Upon any such waiver, such default shall cease to exist, and any Event of Default arising therefrom shall be deemed to have been cured, for every purpose of this Indenture, but no such waiver shall extend to any subsequent or other default or impair any right consequent thereon.

SECTION 514. Undertaking for Costs.

        All parties to this Indenture agree, and each Holder of any Security by his acceptance thereof shall be deemed to have agreed, that any court may in its discretion require, in any suit for the enforcement of any right or remedy under this Indenture, or in any suit against the Trustee for any action taken, suffered or omitted by it as Trustee, the filing by any party litigant, other than the Trustee, in such suit of an undertaking to pay the costs of such suit, and that such court may in its discretion assess reasonable costs, including reasonable attorneys' fees, against any party litigant in such suit, having due regard to the merits and good faith of the claims or defenses made by such party litigant; but the provisions of this Section 514 shall not apply to any suit instituted

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by the Partnership, to any suit instituted by the Trustee, to any suit instituted by any Holder, or group of Holders, holding in the aggregate more than 10% in principal amount of the Outstanding Securities of any series, or to any suit instituted by any Holder for the enforcement of the payment of the principal of, or premium, if any, or interest on any Security on or after the Stated Maturity or Maturities expressed in such Security (or, in the case of redemption, on or after the Redemption Date).

SECTION 515. Waiver of Usury, Stay or Extension Laws.

        The Partnership covenants (to the extent that it may lawfully do so) that it will not at any time insist upon, or plead, or in any manner whatsoever claim or take the benefit or advantage of, any usury, stay or extension law wherever enacted, now or at any time hereafter in force, which may affect the covenants or the performance of this Indenture; and the Partnership (to the extent that it may lawfully do so) hereby expressly waives all benefit or advantage of any such law and covenants that it will not hinder, delay or impede the execution of any power herein granted to the Trustee, but will suffer and permit the execution of every such power as though no such law had been enacted.

ARTICLE VI
THE TRUSTEE

SECTION 601. Certain Duties and Responsibilities.

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SECTION 602. Notice of Defaults.

        Within 90 days after the occurrence of any default hereunder with respect to the Securities of any series, the Trustee shall transmit by mail to all Holders of Securities of such series, as their names and addresses appear in the Security Register, notice of such default hereunder known to the Trustee, unless such Default shall have been cured or waived; provided, however, that, except in the case of a Default in the payment of the principal of or any premium or interest on any Security of such series or in the payment of any sinking fund installment with respect to Securities of such series, the Trustee shall be protected in withholding such notice if and so long as the board of directors, the executive committee or a trust committee of directors and/or Responsible Officers of the Trustee in good faith determine that the withholding of such notice is in the interest of the Holders of Securities of such series; and, provided, further, that in the case of any Default of the character specified in Section 501(3) with respect to Securities of such series, no such notice to Holders shall be given until at least 90 days after the occurrence thereof.

SECTION 603. Certain Rights of Trustee.

        Subject to the provisions of Section 601:

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SECTION 604. Not Responsible for Recitals or Issuance of Securities.

        The recitals contained herein and in the Securities, except the Trustee's certificates of authentication, shall be taken as the statements of the Partnership, and the Trustee or any Authenticating Agent assumes no responsibility for their correctness. Neither the Trustee nor any Authenticating Agent makes any representations as to the validity or sufficiency of this Indenture or of the Securities. Neither the Trustee nor any Authenticating Agent shall be accountable for the use or application by the Partnership of Securities or the proceeds thereof.

SECTION 605. May Hold Securities.

        The Trustee, any Authenticating Agent, any Paying Agent, any Security Registrar or any other agent of the Partnership, in its individual or any other capacity, may become the owner or pledgee of Securities and, subject to Sections 310(b) and 311 of the Trust Indenture Act and Sections 608, 609 and 613 hereof, may otherwise deal with the Partnership with the same rights it would have if it were not Trustee, Authenticating Agent, Paying Agent, Security Registrar or such other agent.

SECTION 606. Money Held in Trust.

        Money held by the Trustee in trust hereunder need not be segregated from other funds except to the extent required by law. The Trustee shall be under no liability for interest on any money received by it hereunder except as otherwise agreed in writing with the Partnership.

SECTION 607. Compensation and Reimbursement.

        The Partnership agrees

        As security for the performance of the obligations of the Partnership under this Section 607 the Trustee shall have a lien prior to the Securities upon all property and funds held or collected by the Trustee as such, except funds held in trust for the payment of principal of (and premium, if any) or interest on particular Securities.

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        Without limiting any rights available to the Trustee under applicable law, when the Trustee incurs expenses or renders services in connection with an Event of Default specified in Section 501(4) or Section 501(5), the expenses (including the reasonable charges and expenses of its counsel) and the compensation for the services of the Trustee are intended to constitute expenses of administration under any applicable Bankruptcy Law.

        The provisions of this Section 607 shall survive the satisfaction and discharge of this Indenture and the defeasance of the Securities.

SECTION 608. Disqualification; Conflicting Interests.

        Reference is made to Section 310(b) of the Trust Indenture Act. There shall be excluded from the operation of Section 310(b)(1) of the Trust Indenture Act this Indenture with respect to the Securities of more than one series.

SECTION 609. Corporate Trustee Required; Eligibility.

        There shall at all times be a Trustee hereunder which shall be a corporation organized and doing business under the laws of the United States of America, any State thereof or the District of Columbia, authorized under such laws to exercise corporate trust powers, having a combined capital and surplus required by the Trust Indenture Act, subject to supervision or examination by Federal or State authority. If such corporation publishes reports of condition at least annually, pursuant to law or to the requirements of said supervising or examining authority, then for the purposes of this Section 609, the combined capital and surplus of such corporation shall be deemed to be its combined capital and surplus as set forth in its most recent report of condition so published. The Trustee shall not be an obligor upon the Securities or an Affiliate thereof. If at any time the Trustee shall cease to be eligible in accordance with the provisions of this Section 609, it shall resign immediately in the manner and with the effect hereinafter specified in this Article.

SECTION 610. Resignation and Removal; Appointment of Successor.

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then, in any such case, (i) the Partnership by a Board Resolution may remove the Trustee with respect to all Securities, or (ii) subject to Section 514, any Holder who has been a bona fide Holder of a Security for at least six months may, on behalf of himself and all others similarly situated, petition any court of competent jurisdiction for the removal of the Trustee with respect to all Securities and the appointment of a successor Trustee or Trustees.

SECTION 611. Acceptance of Appointment by Successor.

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SECTION 612. Merger, Conversion, Consolidation or Succession to Business.

        Any corporation into which the Trustee may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, conversion or consolidation to which the Trustee shall be a party, or any corporation succeeding to all or substantially all the corporate trust business of the Trustee, shall be the successor of the Trustee hereunder, provided such corporation shall be otherwise qualified and eligible under this Article, without the execution or filing of any paper or any further act on the part of any of the parties hereto. In case any Securities shall have been authenticated, but not delivered, by the Trustee then in office, any successor by merger, conversion or consolidation to such authenticating Trustee may adopt such authentication and deliver the Securities so authenticated with the same effect as if such successor Trustee had itself authenticated such Securities.

SECTION 613. Preferential Collection of Claims Against Partnership.

        Reference is made to Section 311 of the Trust Indenture Act. For purposes of Section 311(b) of the Trust Indenture Act,

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SECTION 614. Appointment of Authenticating Agent.

        The Trustee may appoint an Authenticating Agent or Agents with respect to one or more series of Securities which shall be authorized to act on behalf of the Trustee to authenticate Securities of such series issued upon exchange, registration of transfer or partial redemption thereof or pursuant to Section 306, and Securities so authenticated shall be entitled to the benefits of this Indenture and shall be valid and obligatory for all purposes as if authenticated by the Trustee hereunder. Wherever reference is made in this Indenture to the authentication and delivery of Securities by the Trustee or the Trustee's certificate of authentication, such reference shall be deemed to include authentication and delivery on behalf of the Trustee by an Authenticating Agent and a certificate of authentication executed on behalf of the Trustee by an Authenticating Agent. Each Authenticating Agent shall be acceptable to the Partnership and shall at all times be a corporation organized and doing business under the laws of the United States of America, any State thereof or the District of Columbia, authorized under such laws to act as Authenticating Agent, having a combined capital and surplus of not less than $50,000,000 and subject to supervision or examination by Federal or State authority. If such Authenticating Agent publishes reports of condition at least annually, pursuant to law or to the requirements of said supervising or examining authority, then for the purposes of this Section 614, the combined capital and surplus of such Authenticating Agent shall be deemed to be its combined capital and surplus as set forth in its most recent report of condition so published. If at any time an Authenticating Agent shall cease to be eligible in accordance with the provisions of this Section 614, such Authenticating Agent shall resign immediately in the manner and with the effect specified in this Section 614.

        Any corporation into which an Authenticating Agent may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, conversion or consolidation to which such Authenticating Agent shall be a party, or any corporation succeeding to all or substantially all of the corporate agency or corporate trust business of an Authenticating Agent, shall continue to be an Authenticating Agent, provided such corporation shall be otherwise eligible under this Section 614, without the execution or filing of any paper or any further act on the part of the Trustee or the Authenticating Agent.

        An Authenticating Agent may resign at any time by giving written notice thereof to the Trustee and to the Partnership. The Trustee may at any time terminate the agency of an Authenticating Agent by giving written notice thereof to such Authenticating Agent and to the Partnership. Upon receiving such a notice of resignation or upon such a termination, or in case at any time such Authenticating Agent shall cease to be eligible in accordance with the provisions of this Section 614, the Trustee may appoint a successor Authenticating Agent which shall be acceptable to the Partnership and shall mail written notice of such appointment by first-class mail, postage prepaid, to all Holders of Securities of the series with respect to which such Authenticating Agent will serve, as their names and addresses appear in the Security Register. Any successor Authenticating Agent upon acceptance of its appointment hereunder shall become vested with all the rights, powers and duties of its predecessor hereunder, with like effect as if originally named as an Authenticating Agent. No successor Authenticating Agent shall be appointed unless eligible under the provisions of this Section 614.

        Except with respect to an Authenticating Agent appointed at the request of the Partnership, the Trustee agrees to pay to each Authenticating Agent from time to time reasonable compensation for its services under this Section 614, and the Trustee shall be entitled to be reimbursed by the Partnership for such payments, subject to the provisions of Section 607.

        If an appointment with respect to one or more series is made pursuant to this Section 614, the Securities of such series may have endorsed thereon, in addition to the Trustee's certificate of authentication, an alternate certificate of authentication in the following form:

        This is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.

   
  ,
    As Trustee

 
 
By:

 
 
    As Authenticating Agent

 
 
By:

 
 
    Authorized Officer

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ARTICLE VII
HOLDERS' LISTS AND REPORTS BY TRUSTEE AND PARTNERSHIP

SECTION 701. Partnership to Furnish Trustee Names and Addresses of Holders.

        The Partnership will furnish or cause to be furnished to the Trustee

provided, however, that if and so long as the Trustee shall be the Security Registrar, no such list need be furnished with respect to such series of Securities.

SECTION 702. Preservation of Information; Communications to Holders.

        If the Trustee shall elect not to afford such applicants access to such information, the Trustee shall, upon the written request of such applicants, mail to each Holder whose name and address appear in the information preserved at the time by the Trustee in accordance with Section 702(a) a copy of the form of proxy or other communication which is specified in such request, with reasonable promptness after a tender to the Trustee of the material to be mailed and of payment, or provision for the payment, of the reasonable expenses of mailing, unless within five days after such tender the Trustee shall mail to such applicants and file with the Commission, together with a copy of the material to be mailed, a written statement to the effect that, in the opinion of the Trustee, such mailing would be contrary to the best interest of the Holders or would be in violation of applicable law. Such written statement shall specify the basis of such opinion. If the Commission, after opportunity for a hearing upon the objections specified in the written statement so filed, shall enter an order refusing to sustain any of such objections or if, after the entry of an order sustaining one or more of such objections, the Commission shall find, after notice and opportunity for hearing, that all the objections so sustained have been met and shall enter an order so declaring, the Trustee shall mail copies of such material to all such Holders with reasonable promptness after the entry of such order and the renewal of such tender; otherwise the Trustee shall be relieved of any obligation or duty to such applicants respecting their application.

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SECTION 703. Reports by Trustee.

        Any Trustee's report required pursuant to Section 313(a) of the Trust Indenture Act shall be dated as of May 15, and shall be transmitted within 60 days after May 15 of each year, commencing with the year 2002, by mail to all Holders, as their names and addresses appear in the Security Register. A copy of each such report shall, at the time of such transmission to Holders, be filed by the Trustee with each stock exchange or automated quotation system, as applicable, upon which any Securities are listed or traded, with the Commission and with the Partnership. The Partnership will notify the Trustee when any Securities are listed on any stock exchange or traded on any automated quotation system.

SECTION 704. Reports by Partnership.

        The Partnership shall:

        provided, that in each case the delivery of materials to the Trustee by electronic means shall be deemed "furnished" to the Trustee for purposes of this Section 704; and provided further, that the Partnership shall be deemed to have satisfied its obligations under each of (a), (b) and (c) above if it files such information with the Commission (if the Commission will accept such filing) or otherwise makes such financial statements and other information available on or through its web site.

ARTICLE VIII
CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE

SECTION 801. Partnership May Consolidate, Etc., Only on Certain Terms.

        The Partnership shall not consolidate with or merge into any other Person or sell, lease or transfer its properties and assets as, or substantially as, an entirety to, any Person, unless:

        (1)   (A) in the case of a merger, the Partnership is the surviving entity, or (B) the Person formed by such consolidation or into which the Partnership is merged or the Person which acquires by sale or transfer, or which

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leases, the properties and assets of the Partnership as, or substantially as, an entirety expressly assumes, by an indenture supplemental hereto, executed and delivered to the Trustee, in form reasonably satisfactory to the Trustee, the due and punctual payment of the principal of and any premium and interest on all the Securities and the performance or observance of every covenant of this Indenture on the part of the Partnership to be performed or observed and shall have expressly provided for conversion rights in respect of any series of Outstanding Securities with conversion rights;

        (2)   the surviving entity or successor Person is a Person organized and existing under the laws of the United States of America, any State thereof or the District of Columbia;

        (3)   immediately after giving effect to such transaction, no Default or Event of Default shall have occurred and be continuing; and

        (4)   the Partnership has delivered to the Trustee an Officers' Certificate and an Opinion of Counsel, each stating that such consolidation, merger, conveyance, sale, transfer or lease and such supplemental indenture required, if any, comply with this Article and that all conditions precedent herein provided for relating to such transaction have been complied with.

SECTION 802. Successor Substituted.

        Upon any consolidation of the Partnership with, or merger of the Partnership into, any other Person or any sale, transfer or lease of the properties and assets of the Partnership as, or substantially as, an entirety in accordance with Section 801, the successor Person formed by such consolidation or into which the Partnership is merged or to which such sale, transfer or lease is made shall succeed to, and be substituted for, and may exercise every right and power of, the Partnership under this Indenture with the same effect as if such successor Person had been named originally as the Partnership herein, and thereafter, except in the case of a lease, the predecessor Person shall be relieved of all obligations and covenants under this Indenture and the Securities.

ARTICLE IX
SUPPLEMENTAL INDENTURES

SECTION 901. Supplemental Indentures Without Consent of Holders.

        Without the consent of any Holders, the Partnership, when authorized by a Board Resolution, and the Trustee, at any time and from time to time, may enter into one or more indentures supplemental hereto, in form satisfactory to the Trustee, for any of the following purposes:

        (1)   to evidence the succession of another Person to the Partnership and the assumption by any such successor of the covenants of the Partnership herein and in the Securities; or

        (2)   to add to the covenants of the Partnership such further covenants, restrictions, conditions or provisions as the Partnership shall consider to be appropriate for the benefit of the Holders of all or any series of Securities (and if such covenants, restrictions, conditions or provisions are to be for the benefit of less than all series of Securities, stating that such covenants are expressly being included solely for the benefit of such series) or to surrender any right or power herein conferred upon the Partnership and to make the occurrence, or the occurrence and continuance, of a Default in any such additional covenants, restrictions, conditions or provisions an Event of Default permitting the enforcement of all or any of the several remedies provided in this Indenture as herein set forth; provided, that in respect of any such additional covenant, restriction, condition or provision such supplemental indenture may provide for a particular period of grace after default (which period may be shorter or longer than that allowed in the case of other defaults) or may provide for an immediate enforcement upon such an Event of Default or may limit the remedies available to the Trustee upon such an Event of Default or may limit the right of the Holders of a majority in aggregate principal amount of the Securities of such series to waive such an Event of Default; or

        (3)   to add any additional Defaults or Events of Default in respect of all or any series of Securities; or

        (4)   to add to, change or eliminate any of the provisions of this Indenture to such extent as shall be necessary to permit or facilitate the issuance of Securities in bearer form, registrable or not registrable as to principal, and with or without interest coupons; or

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        (5)   to change or eliminate any of the provisions of this Indenture, provided that any such change or elimination shall become effective only when there is no Security Outstanding of any series created prior to the execution of such supplemental indenture which is entitled to the benefit of such provision; or

        (6)   to establish the form or terms of Securities of any series as permitted by Sections 201 and 301, including to reopen any series of any Securities as permitted under Section 301; or

        (7)   to evidence and provide for the acceptance of appointment hereunder by a successor Trustee with respect to the Securities of one or more series and to add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one Trustee, pursuant to the requirements of Section 611(b); or

        (8)   to cure any ambiguity, to correct or supplement any provision herein which may be inconsistent with any other provision herein, to comply with any applicable mandatory provision of law or to make any other provisions with respect to matters or questions arising under this Indenture which shall not adversely affect the interests of the Holders of Securities of any series in any material respect; or

        (9)   to modify, eliminate or add to the provisions of this Indenture to such extent as shall be necessary to effect the qualification of this Indenture under the Trust Indenture Act or under any similar federal statute subsequently enacted, and to add to this Indenture such other provisions as may be expressly required under the Trust Indenture Act.

        The Trustee is hereby authorized to join with the Partnership in the execution of any such supplemental indenture, to make any further appropriate agreements and stipulations which may be therein contained and to accept the conveyance, transfer, assignment, mortgage or pledge of any property thereunder, but the Trustee shall not be obligated to enter into any such supplemental indenture which affects the Trustee's own rights, duties or immunities under this Indenture or otherwise.

SECTION 902. Supplemental Indentures with Consent of Holders.

        With the consent of the Holders of not less than a majority in aggregate principal amount of the Outstanding Securities of all series affected by such supplemental indenture, by Act of said Holders delivered to the Partnership and the Trustee, the Partnership, when authorized by a Board Resolution, and the Trustee may enter into an indenture or indentures supplemental hereto for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this Indenture or of modifying in any manner the rights of the Holders of Securities of such series under this Indenture; provided, however, that no such supplemental indenture shall, without the consent of the Holder of each Outstanding Security affected thereby,

        (1)   change the Stated Maturity of the principal of, or any installment of principal of or interest on, any Security, or reduce the principal amount thereof or the rate of interest thereon or any premium payable upon the redemption thereof, or reduce the amount of the principal of an Original Issue Discount Security that would be due and payable upon a declaration of acceleration of the Maturity thereof pursuant to Section 502, or change any Place of Payment where, or the coin or currency in which, any Security or any premium or the interest thereon is payable, or impair the right to institute suit for the enforcement of any such payment on or after the Stated Maturity thereof (or, in the case of redemption, on or after the Redemption Date), or

        (2)   modify the provisions of this Indenture in a manner adversely affecting any right to convert or exchange any Security into another security; or

        (3)   reduce the percentage in principal amount of the Outstanding Securities of any series, the consent of whose Holders is required for any such supplemental indenture, or the consent of whose Holders is required for any waiver (of compliance with certain provisions of this Indenture or certain defaults hereunder and their consequences) provided for in this Indenture, or

        (4)   modify any of the provisions of this Section 902, Section 513 or Section 1006, except to increase any such percentage or to provide that certain other provisions of this Indenture cannot be modified or waived without the consent of the Holder of each Outstanding Security affected thereby, provided, however, that this clause (4) shall not be deemed to require the consent of any Holder with respect to changes in the references to

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"the Trustee" and concomitant changes in this Section 902, or the deletion of this proviso, in accordance with the requirements of Sections 611(b) and 901(7).

A supplemental indenture which changes or eliminates any covenant or other provision of this Indenture which has expressly been included solely for the benefit of one or more particular series of Securities, or which modifies the rights of the Holders of Securities of such series with respect to such covenant or other provision, shall be deemed not to affect the rights under this Indenture of the Holders of Securities of any other series.

        It shall not be necessary for any Act of Holders under this Section 902 to approve the particular form of any proposed supplemental indenture, but it shall be sufficient if such Act shall approve the substance thereof.

SECTION 903. Execution of Supplemental Indentures.

        In executing, or accepting the additional trusts created by, any supplemental indenture permitted by this Article or the modifications thereby of the trusts created by this Indenture, the Trustee shall be entitled to receive, and (subject to Section 601) shall be fully protected in relying upon, an Opinion of Counsel stating that the execution of such supplemental indenture is authorized or permitted by this Indenture. The Trustee may, but shall not be obligated to, enter into any such supplemental indenture which affects the Trustee's own rights, duties or immunities under this Indenture or otherwise.

SECTION 904. Effect of Supplemental Indentures.

        Upon the execution of any supplemental indenture under this Article, this Indenture shall be modified in accordance therewith, and such supplemental indenture shall form a part of this Indenture for all purposes; and every Holder of Securities theretofore or thereafter authenticated and delivered hereunder shall be bound thereby.

SECTION 905. Conformity with Trust Indenture Act.

        Every supplemental indenture executed pursuant to this Article shall conform to the requirements of the Trust Indenture Act as then in effect.

SECTION 906. Reference in Securities to Supplemental Indentures.

        Securities of any series authenticated and delivered after the execution of any supplemental indenture pursuant to this Article may, and shall if required by the Trustee, bear a notation in form approved by the Trustee as to any matter provided for in such supplemental indenture. If the Partnership shall so determine, new Securities of any series so modified as to conform, in the opinion of the Trustee and the Partnership, to any such supplemental indenture may be prepared and executed by the Partnership and authenticated and delivered by the Trustee in exchange for Outstanding Securities of such series.

ARTICLE X
COVENANTS

SECTION 1001. Payment of Principal, Premium and Interest.

        The Partnership covenants and agrees for the benefit of each series of Securities that it will duly and punctually pay the principal of and any premium and interest on the Securities of that series in accordance with the terms of the Securities and this Indenture.

SECTION 1002. Maintenance of Office or Agency.

        The Partnership will maintain in [                        ], and in each other Place of Payment for any series of Securities an office or agency where Securities of that series may be presented or surrendered for payment, where Securities of that series may be surrendered for registration of transfer or exchange and where notices and demands to or upon the Partnership in respect of the Securities of that series and this Indenture may be served. The Partnership will give prompt written notice to the Trustee of the location, and any change in the location, of such office or agency. If at any time the Partnership shall fail to maintain any such required office or

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agency or shall fail to furnish the Trustee with the address thereof, such presentations, surrenders, notices and demands may be made or served at the Corporate Trust Office of the Trustee, and the Partnership hereby appoints the Trustee as its agent to receive all such presentations, surrenders, notices and demands.

        The Partnership may also from time to time designate one or more other offices or agencies where the Securities of one or more series may be presented or surrendered for any or all such purposes and may from time to time rescind such designations; provided, however, that no such designation or rescission shall in any manner relieve the Partnership of its obligation to maintain an office or agency in [                        ], and in each other Place of Payment for Securities of any series for such purposes. The Partnership will give prompt written notice to the Trustee of any such designation or rescission and of any change in the location of any such other office or agency.

        Except as otherwise specified with respect to a series of Securities as contemplated by Section 301, the Partnership hereby initially designates as the Place of Payment for each series of Securities The City and State of New York, and initially appoints the Trustee at its Corporate Trust Office as the Partnership's office or agency for each such purpose in such city.

SECTION 1003. Money for Securities Payments to Be Held in Trust.

        If the Partnership or any of its Subsidiaries shall at any time act as Paying Agent with respect to any series of Securities, it will, on or before each due date of the principal of and any premium or interest on any of the Securities of that series, segregate and hold in trust for the benefit of the Persons entitled thereto a sum sufficient to pay the principal and any premium and interest so becoming due until such sums shall be paid to such Persons or otherwise disposed of as herein provided and will promptly notify the Trustee of its action or failure so to act.

        Whenever the Partnership shall have one or more Paying Agents for any series of Securities, it will, on or prior to each due date of the principal of and any premium or interest on any Securities of that series, deposit with a Paying Agent a sum sufficient to pay the principal and any premium or interest so becoming due, such sum to be held in trust for the benefit of the Persons entitled to such principal, premium or interest, and (unless such Paying Agent is the Trustee) the Partnership will promptly notify the Trustee of its action or failure so to act. For purposes of this Section 1003, should a due date for principal of and any premium or interest on, or sinking fund payment with respect to any series of Securities not be on a Business Day, such payment shall be due on the next Business Day without any interest for the period from the due date until such Business Day.

        The Partnership will cause each Paying Agent for any series of Securities other than the Trustee to execute and deliver to the Trustee an instrument in which such Paying Agent shall agree with the Trustee, subject to the provisions of this Section 1003, that such Paying Agent will:

        (1)   hold all sums held by it for the payment of the principal of (and premium, if any) or interest, if any, on Securities of that series in trust for the benefit of the Persons entitled thereto until such sums shall be paid to such Persons or otherwise disposed of as herein provided;

        (2)   give the Trustee notice of any default by the Partnership (or any other obligor upon the Securities of that series) in the making of any payment of principal (and premium, if any) or interest, if any, on the Securities of that series; and

        (3)   during the continuance of any such default, upon the written request of the Trustee, forthwith pay to the Trustee all sums so held in trust by such Paying Agent.

        The Partnership may at any time, for the purpose of obtaining the satisfaction and discharge of this Indenture or for any other purpose, pay, or by Partnership Order direct any Paying Agent to pay, to the Trustee all sums held in trust by the Partnership or such Paying Agent, such sums to be held by the Trustee upon the same trusts as those upon which such sums were held by the Partnership or such Paying Agent; and, upon such payment by any Paying Agent to the Trustee, such Paying Agent shall be released from all further liability with respect to such money.

        Subject to any applicable escheat or abandoned property laws, any money deposited with the Trustee or any Paying Agent, or then held by the Partnership, in trust for the payment of the principal of and any premium or

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interest on any Security of any series and remaining unclaimed for one year after such principal and any premium or interest has become due and payable shall be paid to the Partnership on Partnership Request, or (if then held by the Partnership) shall be discharged from such trust; and the Holder of such Security shall thereafter, as an unsecured general creditor, look only to the Partnership for payment thereof, and all liability of the Trustee or such Paying Agent with respect to such trust money, and all liability of the Partnership as trustee thereof, shall thereupon cease; provided, however, that the Trustee or such Paying Agent, before being required to make any such repayment, may at the expense of the Partnership cause to be published once, in a newspaper published in the English language, customarily published on each Business Day and of general circulation in the Borough of Manhattan, The City of New York, notice that such money remains unclaimed and that, after a date specified therein, which shall not be less than 30 days from the date of such publication, any unclaimed balance of such money then remaining will be repaid to the Partnership.

SECTION 1004. Statement by Officers as to Default.

        Annually, within 150 days after the close of each fiscal year beginning with the fiscal year ending December 31, 2002, the Partnership will deliver to the Trustee a brief certificate (which need not include the statements set forth in Section 103) from the principal executive officer, principal financial officer or principal accounting officer of the General Partner of the Partnership as to his or her knowledge of the Partnership's compliance (without regard to any period of grace or requirement of notice provided herein) with all conditions and covenants under the Indenture and, if the Partnership shall be in Default, specifying all such Defaults and the nature and status thereof of which such officer has knowledge.

SECTION 1005. Existence.

        Subject to Article VIII, the Partnership will do or cause to be done all things necessary to preserve and keep in full force and effect its existence, rights (charter and statutory) and franchises; provided, however, that the Partnership shall not be required to preserve any such right or franchise if it shall determine that the preservation thereof is no longer desirable in the conduct of the business of the Partnership.

SECTION 1006. Waiver of Certain Covenants.

        The Partnership may omit in any particular instance to comply with any term, provision or condition set forth in Section 1005 with respect to the Securities of any series if before the time for such compliance the Holders of at least a majority in aggregate principal amount of the Outstanding Securities of all affected series (voting as one class) shall, by Act of such Holders, either waive such compliance in such instance or generally waive compliance with such term, provision or condition, but no such waiver shall extend to or affect such term, provision or condition except to the extent so expressly waived, and, until such waiver shall become effective, the obligations of the Partnership and the duties of the Trustee in respect of any such term, provision or condition shall remain in full force and effect.

        A waiver which changes or eliminates any term, provision or condition of this Indenture which has expressly been included solely for the benefit of one or more particular series of Securities, or which modifies the rights of the Holders of Securities of such series with respect to such term, provision or condition, shall be deemed not to affect the rights under this Indenture of the Holders of Securities of any other series.

SECTION 1007. Additional Amounts.

        If the Securities of a series provide for the payment of additional amounts (as provided in Section 301(18)), at least 10 days prior to the first Interest Payment Date with respect to that series of Securities and at least 10 days prior to each date of payment of principal of, premium, if any, or interest on the Securities of that series if there has been a change with respect to the matters set forth in the below-mentioned Officers' Certificate, the Partnership shall furnish to the Trustee and the principal paying agent, if other than the Trustee, an Officers' Certificate instructing the Trustee and such paying agent whether such payment of principal of, premium, if any, or interest on the Securities of that series shall be made to holders of the Securities of that series without withholding or deduction for or on account of any tax, assessment or other governmental charge described in the Securities of that series. If any such withholding or deduction shall be required, then such Officers' Certificate

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shall specify by country the amount, if any, required to be withheld or deducted on such payments to such holders and shall certify the fact that additional amounts will be payable and the amounts so payable to each holder, and the Partnership shall pay to the Trustee or such paying agent the additional amounts required to be paid by this Section 1007. The Partnership covenants to indemnify the Trustee and any paying agent for, and to hold them harmless against, any loss, liability or expense reasonably incurred without negligence or bad faith on their part arising out of or in connection with actions taken or omitted by any of them in reliance on any Officers' Certificate furnished pursuant to this Section 1007.

        Whenever in this Indenture there is mentioned, in any context, the payment of the principal of or any premium, interest or any other amounts on, or in respect of, any Securities of any series, such mention shall be deemed to include mention of the payment of additional amounts provided by the terms of such series established hereby or pursuant hereto to the extent that, in such context, additional amounts are, were or would be payable in respect thereof pursuant to such terms, and express mention of the payment of additional amounts (if applicable) in any provision hereof shall not be construed as excluding the payment of additional amounts in those provisions hereof where such express mention is not made.

ARTICLE XI
REDEMPTION OF SECURITIES

SECTION 1101. Applicability of Article.

        Securities of any series which are redeemable before their Stated Maturity shall be redeemable in accordance with their terms and (except as otherwise specified as contemplated by Section 301 for Securities of any series) in accordance with this Article.

SECTION 1102. Election to Redeem; Notice to Trustee.

        The election of the Partnership to redeem any Securities shall be evidenced by a Board Resolution. In case of any redemption at the election of the Partnership of less than all the Securities of any series, the Partnership shall, not less than 30 nor more than 60 days prior to the Redemption Date fixed by the Partnership (unless a shorter notice shall be satisfactory to the Trustee), notify the Trustee of such Redemption Date, of the principal amount of Securities of such series to be redeemed and, if applicable, of the tenor of the Securities to be redeemed. In the case of any redemption of Securities (1) prior to the expiration of any restriction on such redemption provided in the terms of such Securities or elsewhere in this Indenture, or (2) pursuant to an election of the Partnership which is subject to a condition specified in the terms of such Securities, the Partnership shall furnish the Trustee with an Officers' Certificate evidencing compliance with such restriction or condition.

SECTION 1103. Selection by Trustee of Securities to be Redeemed.

        If less than all the Securities of any series are to be redeemed (unless all the Securities of such series and of a specified tenor are to be redeemed), the particular Securities to be redeemed shall be selected not more than 45 days prior to the Redemption Date by the Trustee, from the Outstanding Securities of such series not previously called for redemption, by lottery for redemption of portions (equal to the minimum authorized denomination for Securities of that series or any integral multiple thereof) of the principal amount of Securities of such series of a denomination larger than the minimum authorized denomination for Securities of that series.

        The Trustee shall promptly notify the Partnership in writing of the Securities selected for redemption and, in the case of any Securities selected for partial redemption, the principal amount thereof to be redeemed. If the Securities of any series to be redeemed consist of Securities having different dates on which the principal is payable or different rates of interest, or different methods by which interest may be determined or have any other different tenor or terms, then the Partnership may, by written notice to the Trustee, direct that the Securities of such series to be redeemed shall be selected from among the groups of such Securities having specified tenor or terms and the Trustee shall thereafter select the particular Securities to be redeemed in the manner set forth in the preceding paragraph from among the group of such Securities so specified.

        For all purposes of this Indenture, unless the context otherwise requires, all provisions relating to the redemption of Securities shall relate, in the case of any Securities redeemed or to be redeemed only in part, to the portion of the principal amount of such Securities which has been or is to be redeemed.

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SECTION 1104. Notice of Redemption.

        Notice of redemption shall be given by first-class mail (if international mail, by air mail), postage prepaid, mailed not less than 30 nor more than 60 days prior to the Redemption Date, to each Holder of Securities to be redeemed, at his address appearing in the Security Register.

        All notices of redemption shall state:

        Notice of redemption of Securities to be redeemed shall be given by the Partnership or, at the Partnership's request, by the Trustee in the name and at the expense of the Partnership.

SECTION 1105. Deposit of Redemption Price.

        On or prior to any Redemption Date, the Partnership shall deposit with the Trustee or with a Paying Agent (or, if the Partnership is acting as its own Paying Agent, segregate and hold in trust as provided in Section 1003) an amount of money sufficient to pay the Redemption Price of, and (except if the Redemption Date shall be an Interest Payment Date) accrued interest on, all the Securities which are to be redeemed on that date.

SECTION 1106. Securities Payable on Redemption Date.

        Notice of redemption having been given as aforesaid, the Securities so to be redeemed shall, on the Redemption Date, become due and payable at the Redemption Price therein specified, and from and after such date (unless the Partnership shall default in the payment of the Redemption Price and accrued interest) such Securities shall cease to bear interest. Upon surrender of any such Security for redemption in accordance with said notice, such Security shall be paid by the Partnership at the Redemption Price, together with accrued interest to the Redemption Date; provided, however, that, unless otherwise specified as contemplated by Section 301, installments of interest whose Stated Maturity is on or prior to the Redemption Date shall be payable to the Holders of such Securities, or one or more Predecessor Securities, registered as such at the close of business on the relevant Record Dates according to their terms and the provisions of Section 307.

        If any Security called for redemption shall not be so paid upon surrender thereof for redemption, the principal and any premium shall, until paid, bear interest from the Redemption Date at the rate prescribed therefor in the Security.

SECTION 1107. Securities Redeemed in Part.

        Any Security which is to be redeemed only in part shall be surrendered at a Place of Payment therefor (with, if the Partnership or the Trustee so requires, due endorsement by, or a written instrument of transfer in form satisfactory to the Partnership and the Trustee duly executed by, the Holder thereof or his attorney duly authorized in writing), and the Partnership shall execute, and the Trustee shall authenticate and deliver to the Holder of such Security without service charge, a new Security or Securities of the same series and of like tenor, of any authorized denomination as requested by such Holder, in aggregate principal amount equal to and in exchange for the unredeemed portion of the principal of the Security so surrendered.

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ARTICLE XII
SINKING FUNDS

SECTION 1201. Applicability of Article.

        The provisions of this Article shall be applicable to any sinking fund for the retirement of Securities of a series except as otherwise specified as contemplated by Section 301 for Securities of such series.

        The minimum amount of any sinking fund payment provided for by the terms of Securities of any series is herein referred to as a "mandatory sinking fund payment," and any payment in excess of such minimum amount provided for by the terms of Securities of any series is herein referred to as an "optional sinking fund payment." If provided for by the terms of Securities of any series, the cash amount of any sinking fund payment may be subject to reduction as provided in Section 1202. Each sinking fund payment shall be applied to the redemption of Securities of any series as provided for by the terms of Securities of such series.

SECTION 1202. Satisfaction of Sinking Fund Payments with Securities.

        The Partnership (1) may deliver Outstanding Securities of a series (other than any previously called for redemption), and (2) may apply as a credit Securities of a series which have been redeemed either at the election of the Partnership pursuant to the terms of such Securities or through the application of permitted optional sinking fund payments pursuant to the terms of such Securities, in each case in satisfaction of all or any part of any sinking fund payment with respect to the Securities of such series required to be made pursuant to the terms of such Securities as provided for by the terms of such series; provided that such Securities have not been previously so credited. Such Securities shall be received and credited for such purpose by the Trustee at the Redemption Price specified in such Securities for redemption through operation of the sinking fund and the amount of such sinking fund payment shall be reduced accordingly.

SECTION 1203. Redemption of Securities for Sinking Fund.

        Not less than 45 days prior to each sinking fund payment date for any series of Securities (unless a shorter period shall be satisfactory to the Trustee), the Partnership will deliver to the Trustee an Officers' Certificate specifying the amount of the next ensuing sinking fund payment for that series pursuant to the terms of that series, the portion thereof, if any, which is to be satisfied by payment of cash and the portion thereof, if any, which is to be satisfied by delivering and crediting Securities of that series pursuant to Section 1202 and stating the basis for such credit and that such Securities have not been previously so credited, and will also deliver to the Trustee any Securities to be so delivered. Not less than 30 days before each such sinking fund payment date the Trustee shall select the Securities to be redeemed upon such sinking fund payment date in the manner specified in Section 1103 and cause notice of the redemption thereof to be given in the name of and at the expense of the Partnership in the manner provided in Section 1104. Such notice having been duly given, the redemption of such Securities shall be made upon the terms and in the manner stated in Sections 1106 and 1107.

ARTICLE XIII
DEFEASANCE

SECTION 1301. Applicability of Article.

        The provisions of this Article shall be applicable to each series of Securities except as otherwise specified as contemplated by Section 301 for Securities of such series.

SECTION 1302. Legal Defeasance.

        In addition to discharge of this Indenture pursuant to Section 401, the Partnership shall be deemed to have paid and discharged the entire indebtedness on all the Securities of such a series on the 91st day after the date of the deposit referred to in clause (1) below, and the provisions of this Indenture with respect to the Securities of such series shall no longer be in effect (except as to (i) rights of registration of transfer and exchange of Securities of such series and the Partnership's right of optional redemption, if any, (ii) substitution of mutilated, destroyed, lost or stolen Securities, (iii) rights of Holders of Securities to receive, solely from the trust fund

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described in Section 1304 and as more fully set forth in such Section, payments of principal thereof and interest thereon, upon the original stated due dates therefor or on the specified redemption dates therefor (but not upon acceleration), and remaining rights of the Holders to receive mandatory sinking fund payments, if any, (iv) the rights, obligations, duties and immunities of the Trustee hereunder, and the Partnership's obligations in connection therewith (including, but not limited to, Section 607), (v) the rights, if any, to convert or exchange the Securities of such series, (vi) the rights of the Holders of Securities of such series as beneficiaries hereof with respect to the property so deposited with the Trustee payable to all or any of them, and (vii) the obligations of the Partnership under Section 1002), and the Trustee, at the expense of the Partnership, shall, upon a Partnership Request, execute proper instruments acknowledging the same, if the conditions set forth below are satisfied (hereinafter, "defeasance"):

        For this purpose, such defeasance means that the Partnership and any other obligor upon the Securities of such series shall be deemed to have paid and discharged the entire debt represented by the Securities of such series, which shall thereafter be deemed to be "Outstanding" only for the purposes of Section 1304 and the

49


rights and obligations referred to in clauses (i) through (vii), inclusive, of the first paragraph of this Section 1302, and to have satisfied all its other obligations under the Securities of such series and this Indenture insofar as the Securities of such series are concerned.

        Notwithstanding the foregoing, if an Event of Default specified in Section 501(4) or 501(5), or an event which with lapse of time would become such an Event of Default, shall occur during the period ending on the 91st day after the date of the deposit referred to in clause (1) or, if longer, ending on the day following the expiration of the longest preference period applicable to the Partnership in respect of such deposit, then, effective upon such occurrence, the defeasance pursuant to this Section 1302 and such deposit shall be rescinded and annulled, and the Partnership, the Trustee and the Holders of the Securities of such series shall be restored to their former positions.

SECTION 1303. Covenant Defeasance.

        The Partnership and any other obligor shall be released on the 91st day after the date of the deposit referred to in clause (1) below from its obligations under Sections 704, 801 and 1005, with respect to the Securities of any series on and after the date the conditions set forth below are satisfied (hereinafter, "covenant defeasance"), and the Securities of such series shall thereafter be deemed to be not "Outstanding" for the purposes of any request, demand, authorization, direction, notice, waiver, consent or declaration or other action or Act of Holders (and the consequences of any thereof) in connection with such covenants, but shall continue to be deemed Outstanding for all other purposes hereunder. For this purpose, such covenant defeasance means that, with respect to the Securities of such series, the Partnership may omit to comply with and shall have no liability in respect of any term, condition or limitation set forth in any such Section, whether directly or indirectly by reason of any reference elsewhere herein to such Section or by reason of any reference in such Section to any other provision herein or in any other document and such omission to comply shall not constitute a Default or an Event of Default under Section 501, but, except as specified above, the remainder of this Indenture and the Securities of such series shall be unaffected thereby. The following shall be the conditions to application of this Section 1303:

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        Notwithstanding the foregoing, if an Event of Default specified in Section 501(4) or 501(5), or an event which with lapse of time would become such an Event of Default, shall occur during the period ending on the 91st day after the date of the deposit referred to in clause (1) or, if longer, ending on the day following the expiration of the longest preference period applicable to the Partnership in respect of such deposit, then, effective upon such occurrence, the defeasance pursuant to this Section 1303 and such deposit shall be rescinded and annulled, and the Partnership, the Trustee and the Holders of the Securities of such series shall be restored to their former positions.

SECTION 1304. Application by Trustee of Funds Deposited for Payment of Securities.

        Subject to the provisions of the last paragraph of Section 1003, all moneys or U.S. Government Obligations (including proceeds thereof) deposited with the Trustee pursuant to Section 1302 or 1303 (and all funds earned on such moneys or U.S. Government Obligations) shall be held in trust and applied by it, in accordance with the provisions of such Securities and this Indenture, to the payment, either directly or through any Paying Agent (including the Partnership acting as its own Paying Agent), to the Holders of the particular Securities of such series for the payment or redemption of which such moneys have been deposited with the Trustee, of all sums due and to become due thereon for principal and any premium and interest; but such money need not be segregated from other funds except to the extent required by law. Subject to Sections 1302 and 1303, the Trustee shall promptly pay to the Partnership upon request any excess moneys held by it at any time.

SECTION 1305. Repayment to Partnership.

        The Trustee and any Paying Agent promptly shall pay or return to the Partnership upon Partnership Request any money and U.S. Government Obligations held by them at any time that are not required for the payment of the principal of, premium, if any, and any interest on the Securities of any series for which money or U.S. Government Obligations have been deposited pursuant to Section 1302 or 1303.

        The provisions of the last paragraph of Section 1003 shall apply to any money held by the Trustee or any Paying Agent under this Article that remains unclaimed for one year after the Maturity of any series of Securities for which money or U.S. Government Obligations have been deposited pursuant to Section 1302 or 1303.

        This instrument may executed in any number of counterparts, each of which so executed shall be deemed to be an original, but all such counterparts shall together constitute but one and the same instrument.

ARTICLE XIV
SUBORDINATION OF SECURITIES

SECTION 1401. Securities Subordinated to Senior Debt.

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SECTION 1402. Distribution on Dissolution, Liquidation and Reorganization; Subrogation of Securities.

        Upon any distribution of assets of the Partnership upon any dissolution, winding up, liquidation or reorganization of the Partnership, whether in bankruptcy, insolvency, reorganization or receivership proceedings or upon an assignment for the benefit of creditors or any other marshalling of the assets and liabilities of the Partnership or otherwise (subject to the power of a court of competent jurisdiction to make other equitable provision reflecting the rights conferred in this Indenture upon the Senior Debt of the Partnership and the holders thereof with respect to the Securities and the Holders thereof by a lawful plan or reorganization under applicable bankruptcy law).

52

        Subject to the payment in full of all Senior Debt of the Partnership, the Holders of the Securities shall be subrogated to the rights of the holders of such Senior Debt to receive payments or distributions of cash, property or securities of the Partnership applicable to Senior Debt of the Partnership until the principal, premium, interest, and any interest thereon, of or on the Securities shall be paid in full and no such payments or distributions to the Holders of the Securities of cash, property or securities otherwise distributable to the Senior Debt of the Partnership shall, as between the Partnership, its creditors other than the holders of Senior Debt of the Partnership, and the Holders of the Securities, be deemed to be a payment by the Partnership to or on account of the Securities. It is understood that the provisions of this Article are and are intended solely for the purpose of defining the relative rights of the Holders of the Securities, on the one hand, and the holders of Senior Debt of the Partnership, on the other hand. Nothing contained in this Article or elsewhere in this Indenture or in the Securities is intended to or shall impair, as between the Partnership, its creditors other than the holders of Senior Debt of the Partnership, and the Holders of the Securities, the obligation of the Partnership, which is unconditional and absolute, to pay to the Holders of the Securities the principal, premium, interest, and any interest thereon, of or on the Securities as and when the same shall become due and payable in accordance with their terms, or to affect the relative rights of the Holders of the Securities and creditors of the Partnership other than the holders of Senior Debt of the Partnership, nor shall anything herein or in the Securities prevent the Trustee or the Holder of any Security from exercising all remedies otherwise permitted by applicable law upon default under this Indenture, subject to the rights, if any, under this Article of the holders of such Senior Debt in respect of cash, property or securities of the Partnership received upon the exercise of any such remedy. Upon any payment or distribution of assets of the Partnership referred to in this Article, the Trustee shall be entitled to conclusively rely upon a certificate of the liquidating trustee or agent or other person making any distribution to the Trustee for the purpose of ascertaining the persons entitled to participate in such distribution, the holders of Senior Debt of the Partnership and other indebtedness of the Partnership, the amount thereof or payable thereon, the amount or amounts paid or distributed thereon, and all other facts pertinent thereto or to this Article.

        The Trustee, however, shall not be deemed to owe any fiduciary duty to the holders of Senior Debt of the Partnership. The Trustee shall not be liable to any such holder if it shall pay over or distribute to or on behalf of Holders of Securities or the Partnership moneys or assets to which any holder of Senior Debt of the Partnership shall be entitled by virtue of this Article. The rights and claims of the Trustee under Section 607 shall not be subject to the provisions of this Article.

        If the Trustee or any Holder of Securities does not file a proper claim or proof of debt in the form required in any proceeding referred to above prior to 30 days before the expiration of the time to file such claim in such proceeding, then the holder of any Senior Debt of the Partnership is hereby authorized, and has the right, to file an appropriate claim or claims for or on behalf of such Holder of Securities.

SECTION 1403. Payments on Securities Permitted.

        Nothing contained in this Indenture or in any of the Securities shall (1) affect the obligation of the Partnership to make, or prevent the Partnership from making, at any time except as provided in Sections 1401 and 1402, payments of principal, premium, interest, and any interest thereon, of or on the Securities or (2) prevent the application by the Trustee of any moneys deposited with it hereunder to the payment of or on account of the principal, premium, interest or other amounts, and any interest thereon, of or on the Securities unless the Trustee shall have received at its Corporate Trust Office written notice of any event prohibiting the making of such payment two Business Days (A) prior to the date fixed for such payment, (B) prior to the

53


execution of an instrument to satisfy and discharge this Indenture based upon the deposit of funds under Section 401(1)(a), (C) prior to the execution of an instrument acknowledging the defeasance of such Securities pursuant to Section 1302 or (D) prior to any deposit pursuant to clause (1) of Section 1303 with respect to such Securities.

SECTION 1404. Authorization of Holders of Securities to Trustee to Effect Subordination.

        Each Holder of Securities by his acceptance thereof, whether upon original issue or upon transfer or assignment, authorizes and directs the Trustee on his behalf to take such action as may be necessary or appropriate to effectuate the subordination as provided in this Article and appoints the Trustee his attorney-in-fact for any and all such purposes.

SECTION 1405. Notices to Trustee.

        The Partnership shall give prompt written notice to a Responsible Officer of the Trustee located at the Corporate Trust Office of the Trustee of any fact known to the Partnership which would prevent the making of any payment to or by the Trustee in respect of the Securities. Notwithstanding the Provisions of this Article or any other provisions of this Indenture, neither the Trustee nor any Paying Agent (other than the Partnership) shall be charged with knowledge of the existence of any Senior Debt of the Partnership or of any event which would prohibit the making of any payment of moneys to or by the Trustee or such Paying Agent, unless and until the Trustee or such Paying Agent shall have received (in the case of the Trustee, at its Corporate Trust Office) written notice thereof from the Partnership or from the holder of any Senior Debt of the Partnership or from the trustee for or representative of any Senior Debt of the Partnership together with proof satisfactory to the Trustee of such holding of such Senior Debt or of the authority of such trustee or representative; provided, however, that if at least two Business Days prior to the date upon which by the terms hereof any such moneys may become payable for any purpose (including, without limitation, the payment of the principal, premium, interest, of or on any Security, or any interest thereon) or the date on which the Trustee shall execute an instrument acknowledging satisfaction and discharge of this Indenture or the defeasance of Securities pursuant to Section 1302 or the date on which a deposit pursuant to clause (1) of Section 1303 is made, the Trustee shall not have received with respect to such moneys or the moneys deposited with it as a condition to such satisfaction and discharge or defeasance the notice provided for in this Section 1405, then, anything herein contained to the contrary notwithstanding, the Trustee shall have full power and authority to receive such moneys and to apply the same to the purpose for which they were received, and shall not be affected by any notice to the contrary, which may be received by it on or after such two Business Days prior to such date. The Trustee shall be entitled to conclusively rely on the delivery to it of a written notice by a person representing himself to be a holder of Senior Debt of the Partnership (or a trustee or representative on behalf of such holder) to establish that such a notice has been given by a holder of Senior Debt of the Partnership or a trustee or representative on behalf of any such holder. In the event that the Trustee determines in good faith that further evidence is required with respect to the right of any Person as a holder of Senior Debt of the Partnership to participate in any payment or distribution pursuant to this Article, the Trustee may request such Person to furnish evidence to the reasonable satisfaction of the Trustee as to the amount of Senior Debt of the Partnership held by such Person, the extent to which such Person is entitled to participate in such payment or distribution and any other facts pertinent to the rights of such Person under this Article and, if such evidence is not furnished, the Trustee may defer any payment to such Person pending judicial determination as to the right of such Person to receive such payment.

SECTION 1406. Trustee as Holder of Senior Debt.

        The Trustee shall be entitled to all the rights set forth in this Article in respect of any Senior Debt of the Partnership at any time held by it to the same extent as any other holder of Senior Debt of the Partnership and nothing in this Indenture shall be construed to deprive the Trustee of any of its rights as such holder.

SECTION 1407. Modification of Terms of Senior Debt.

        Any renewal or extension of the time of payment of any Senior Debt of the Partnership or the exercise by the holders of Senior Debt of the Partnership of any of their rights under any instrument creating or evidencing

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such Senior Debt, including without limitation the waiver of default thereunder, may be made or done all without notice to or assent from Holders of the Securities or the Trustee.

        No compromise, alteration, amendment, modification, extension, renewal or other change of, or waiver, consent or other action in respect of, any liability or obligation under or in respect of, or of any of the terms, covenants or conditions of any indenture or other instrument under which any Senior Debt of the Partnership is outstanding or of such Senior Debt, whether or not such release is in accordance with the provisions of any applicable document, shall in any way alter or affect any of the provisions of this Article or of the Securities relating to the subordination thereof.

        IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be duly executed, all as of the day and year first above written.

    TC PIPELINES, LP,

 
 
By:
TC PipeLines GP, Inc.
Its General Partner

 
 
By:

 
 
Name:

 
 
Title:

 
 
[                        ], as Trustee

 
 
By:

 
 
Name:

 
 
Title:

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EXHIBIT 4.3

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EXHIBIT 5.1




[ANDREWS KURTH LLP LOGO]

 

600 Travis, Suite 4200
Houston, Texas 77002
713.220.4200 Phone
713.220.4285 Fax
andrewskurth.com

        December 22, 2004

Board of Directors
TC PipeLines GP, Inc.
450 - 1st Street S.W.
Calgary, Alberta
Canada, T2P 5H1

Ladies and Gentlemen:

        We have acted as special counsel to TC PipeLines, LP, a Delaware limited partnership (the "Partnership"), and TC PipeLines GP, Inc., a Delaware corporation and the general partner of the Partnership (the "General Partner"), in connection with the preparation of a registration statement on Form S-3 (the "Registration Statement"), filed with the Securities and Exchange Commission (the "Commission") pursuant to the Securities Act of 1933, as amended (the "Act"). The Registration Statement relates to the offering from time to time, as set forth in the Registration Statement, the form of prospectus contained therein (the "Prospectus") and one or more supplements to the Prospectus (each, a "Prospectus Supplement"), of, among other securities, (i) common units representing limited partnership interests in the Partnership ("Common Units") and (ii) debt securities ("Debt Securities") of the Partnership, and together to be offered by the Partnership and having an aggregate initial public offering price not to exceed $200,000,000, in the case of both clauses (i) and (ii) on terms to be determined at the time of the offering. The Registration Statement also relates to the offering, by the General Partner and TransCan Northern, Ltd. (collectively, the "Selling Unitholders"), of up to an aggregate of 2,809,306 and 2,800,000 Common Units, respectively (the "Selling Unitholder Units"), which may be sold by the Selling Unitholders from time to time pursuant to Rule 415 under the Securities Act. The Common Units, the Debt Securities and the Selling Unitholder Units are each individually referred to herein as a "Security" and collectively referred to herein as the "Securities." All capitalized terms which are not defined herein shall have the meanings assigned to them in the Registration Statement or in the applicable Indenture, as the case may be.

        The Debt Securities will be issued pursuant to (i) a senior indenture (the "Senior Indenture") or (ii) a subordinated indenture (the "Subordinated Indenture" and, together with the Senior Indenture, the "Indentures"), to be entered into between the Partnership and a financial institution to be named therein, as trustee (the "Trustee"), substantially in the forms attached as Exhibits 4.2 and 4.3 to the Registration Statement, and each as the same may hereafter be supplemented from time to time, among other things at the time of and in connection with the issuance of the Debt Securities.

        In arriving at the opinions expressed below, we have examined (i) the Certificate of Limited Partnership and the Amended and Restated Agreement of Limited Partnership of the Partnership, as amended to date (the "Limited Partnership Agreement"), (ii) the Certificate of Incorporation and the Bylaws of the General Partner, as amended to date, (iii) the Registration Statement, (iv) the Prospectus, (v) the Senior Indenture and the Subordinated Indenture, (vi) certified copies of certain resolutions adopted by the Board of Directors of the General Partner and (vii) the originals or copies certified or otherwise identified to our satisfaction of such other instruments and other certificates of public officials, officers and representatives of the Partnership and the General Partner and such other persons, and we have made such investigations of law, as we have deemed appropriate as a basis for the opinions expressed below.

        In rendering the opinions expressed below, we have assumed and have not verified (i) the genuineness of the signatures on all documents that we have examined, (ii) the legal capacity of all natural persons, (iii) the authenticity of all the documents supplied to us as originals, and (iv) the conformity to the authentic originals of all documents supplied to us as certified, photostatic, faxed or conformed copies. In conducting our examination


of documents executed by parties other than the Partnership and the General Partner, we have assumed that such parties had the power, corporate or other, to enter into and perform all obligations thereunder and have also assumed the due authorization by all requisite action, corporate or other, and the due execution and delivery by such parties of such documents and that, to the extent such documents purport to constitute agreements, such documents constitute valid and binding obligations of such parties.

        In rendering the opinions expressed below with respect to the Securities, we have assumed that (i) any Supplemental Indenture to either Indenture and any Board Resolution and/or any Officers' Certificate pursuant to either Indenture, pursuant to which, in any such case, any Debt Securities are issued will comply with such Indenture as theretofore supplemented, and the form and terms of such Debt Securities will comply with such Indenture as then supplemented (including by any such Supplemental Indenture) and any such Board Resolution and/or Officers' Certificate; and (ii) the form and terms of such Debt Securities, when established, and the issuance, sale and delivery thereof by the Partnership, and its incurrence and performance of its obligations thereunder or in respect thereof in accordance with the terms thereof, and any such Board Resolution, will comply with, and will not violate, its Certificate of Limited Partnership or the Limited Partnership Agreement, or any applicable law, rule, regulation, order, judgment, decree, award, or agreement binding upon the Partnership, or to which the issuance, sale and delivery of such Debt Securities, or the incurrence and performance of such obligations, may be subject, or violate any applicable public policy, or be subject to any defense in law or equity, and (without limiting the generality of the foregoing) Section 5-501.6.b of the New York General Obligations Law will apply in the case of all such Debt Securities. In addition, we have assumed the receipt by each person to whom or for whose benefit a Security is to be issued (collectively, the "Holders") of a certificate for such Security or the receipt by the Depository Trust Company, acting as agent, on behalf of all Holders of the class or series of Securities of which such Security is one, of a global security then evidencing such Securities, and the issuance and sale of and payment for the Securities so acquired, in accordance with the applicable purchase, underwriting or similar agreement approved by the Board of Directors of the General Partner (the "Board") and the Registration Statement (including the Prospectus and the applicable Prospectus Supplement)

        With respect to the Selling Unitholder Units, we have also assumed that (i) the Registration Statement and any amendments thereto (including post-effective amendments) will have become effective under the Securities Act and comply with all applicable laws, (ii) a Prospectus Supplement will have been prepared in accordance with and shall comply with all applicable laws and will have been filed with the SEC describing the Selling Unitholder Units offered thereby, (iii) all Selling Unitholder Units offered will be offered and sold in compliance with applicable federal and state securities laws and solely in the manner stated in the Registration Statement and the appropriate Prospectus Supplement, (vii) there shall be no change in law affecting the validity of any of the Selling Unitholder Units (between the date hereof and the date of issuance and sale of such Selling Unitholder Units), and (viii) all parties to agreements involving the offer or sale of the Selling Unitholder Units will perform their obligations thereunder in compliance with the terms of such documents.

        Based on and subject to the foregoing, and subject also to the limitations and other qualifications set forth below, we are of the opinion that:

2

        Our opinions in paragraphs 3 and 4 above are subject to applicable bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfer or conveyance), reorganization, moratorium and other similar laws affecting creditors' rights generally and to general principles of equity (regardless of whether enforcement is sought in a proceeding in equity or at law), including, without limitation, (a) the possible unavailability of specific performance, injunctive relief or any other equitable remedy and (b) concepts of materiality, reasonableness, good faith and fair dealing. We express no opinion as to any provisions relating to separability, purporting to disregard any course of dealing or setting forth any standard for performance that may not be objectively determinable.

        We express no opinion other than as to the federal laws of the United States of America, the contract laws of the State of New York and the Delaware Act. We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the reference to this firm under the heading "Legal" in the Prospectus. In giving this consent we do not admit that we are "experts" under the Act, or the rules and regulations of the Commission issued thereunder, with respect to any part of the Registration Statement, including this exhibit.

                                                                                            Very truly yours,

                                                                                            /s/ Andrews Kurth LLP

3



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EXHIBIT 8.1

Andrews Kurth LLP
600 Travis Street, Suite 4200
Houston, Texas 77002

December 22, 2004

Board of Directors
TC PipeLines GP, Inc.
450 1st Street S.W.
Calgary, Alberta
Canada, T2P 5H1

Ladies and Gentlemen:

        We have acted as special counsel in connection with the Registration Statement on Form S-3 (the "Registration Statement") of TC PipeLines, L.P., a Delaware limited partnership (the "Partnership"), relating to the registration of the offering and sale (the "Offering") of common units ("Common Units") and debt securities ("Debt Securities") of the Partnership to be issued and sold by the Partnership from time to time pursuant to Rule 415 under the Securities Act of 1933, as amended (the "Act"), for an aggregate offering price not to exceed $250,000,000, and of Common Units by the selling unitholders named in the Prospectus, on terms to be determined at the time of the offering. The Common Units and the Debt Securities are collectively referred to herein as the "Securities." In connection therewith, we have participated in the preparation of the discussion set forth under the caption "Tax Considerations" (the "Discussion") in the Registration Statement. Capitalized terms used and not otherwise defined herein are used as defined in the Registration Statement.

        The Discussion, subject to the qualifications and assumptions stated in the Discussion and the limitations and qualifications set forth herein, constitutes our opinion as to the material United States federal income tax consequences for purchasers of the Common Units pursuant to the Offering.

        A discussion with regard to the material United States federal income tax consequences, if any, for purchasers of the Debt Securities pursuant to the Offering will be included in a prospectus supplement relating to the issuance of such securities. An opinion with respect to any such discussion will be filed as an exhibit to a Current Report on Form 8-K of the Partnership.

        This opinion letter is limited to the matters set forth herein, and no opinions are intended to be implied or may be inferred beyond those expressly stated herein. Our opinion is rendered as of the date hereof and we assume no obligation to update or supplement this opinion or any matter related to this opinion to reflect any change of fact, circumstances, or law after the date hereof. In addition, our opinion is based on the assumption that the matter will be properly presented to the applicable court. Furthermore, our opinion is not binding on the Internal Revenue Service or a court. In addition, we must note that our opinion represents merely our best legal judgment on the matters presented and that others may disagree with our conclusion. There can be no assurance that the Internal Revenue Service will not take a contrary position or that a court would agree with our opinion if litigated.

        We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the references to our firm and this opinion contained in the Discussion. In giving this consent, however, we do not hereby admit that we are within the category of persons whose consent is required under section 7 of the Act, or the rules and regulations of the Securities and Exchange Commission thereunder.

    Very truly yours,

 
 
/s/ ANDREWS KURTH LLP



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EXHIBIT 8.1

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EXHIBIT 12.1

Statement of Computation of Ratio of Earnings to Fixed Charges

 
    
   Year ended December 31,
   Year ended December 31,
    
  
 
   May 28(1)-
December 31,
1999
   Quarter ended
September 30,
2004
  
 
   2000
   2001
   2002
   2003
  
Earnings                          
  Income from Continuing Operations   (699 ) (1,838 ) (2,224 ) (1,950 ) (1,910 ) (1,789 )
  Fixed Charges   —   596   1,125   426   200   363  
  Distributions from Equity Investees   12,124   41,971   45,358   47,493   49,820   41,559  
   
 
 
 
 
 
 
  Total Earnings   11,425   40,729   44,259   45,969   48,110   40,133  
   
 
 
 
 
 
 
Fixed Charges                          
  Interest expense   — (2) 596 (3) 1,125   426   200   363  
   
 
 
 
 
 
 
  Total Fixed Charges   —   596   1,125   426   200   363  
   
 
 
 
 
 
 
Ratio: Earnings/Fixed Charges   N/A   68.34   39.34   107.91   240.55   110.56  
   
 
 
 
 
 
 
(1)
Commencement of operations.
(2)
We did not incur interest expense in the period May 28 - December 31, 1999.

(3)
On September 1, 2000 we drew on our third party revolving credit facility to fund a portion of our acquisition of a 49% general partner interest in Tuscarora and incurred interest expense for four months in 2000.



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EXHIBIT 23.1

GRAPHIC            
    KPMG LLP        
    Chartered Accountants   Telephone   (403) 691-8000
    1200-205 5 Avenue SW   Fax   (403) 691-8008
    Calgary AB    T2P 4B9   Internet   www.kpmg.ca

    
 
 
 
 
 
 

Consent of Independent Registered Chartered Accountants

TC PipeLines, LP:

We consent to the incorporation by reference in the registration statement on Form S-3 of TC PipeLines, LP, dated December 22, 2004, of our report dated March 4, 2004, with respect to the balance sheets of TC PipeLines, LP as of December 31, 2003 and 2002, and the related statements of income, comprehensive income, cash flows and changes in partners' equity for each of the years in the three-year period ended December 31, 2003, which report appears in TC PipeLines, LP annual report on Form 10-K for the year ended December 31, 2003, and to the reference to our firm under the heading "Experts" in the prospectus.


 
 
/s/  KPMG LLP      
KPMG LLP

Calgary, Canada
December 22, 2004

    KPMG LLP, a Canadian owned limited liability partnership, is the Canadian
member firm of KPMG International, a Swiss association		       



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EXHIBIT 23.1

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EXHIBIT 23.2

GRAPHIC

Consent of Independent Registered Public Accounting Firm

Northern Border Pipeline Company:

We consent to the incorporation by reference in the registration statement on Form S-3 of TC PipeLines, LP, dated December 22, 2004, of our report dated January 27, 2004, with respect to the balance sheets of Northern Border Pipeline Company as of December 31, 2003 and 2002, and the related statements of income, comprehensive income, cash flows, and changes in partners' equity for each of the years in the three-year period ended December 31, 2003, and the related financial statement schedule, which report appears in TC PipeLines, LP annual report on Form 10-K for the year ended December 31, 2003, and to the reference to our firm under the heading "Experts" in the prospectus.

GRAPHIC

Omaha, Nebraska
December 22, 2004

    KPMG LLP, a U.S. limited liability partnership, is the U.S.
member firm of KPMG International, a Swiss cooperative.		       



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EXHIBIT 23.2