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As filed with the Securities and Exchange Commission on June 12, 2014

Registration No. 333-            

United States
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM F-10
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

CENOVUS ENERGY INC.
(Exact name of Registrant as specified in its charter)

Canada
(Province or other jurisdiction of incorporation or organization)

1311
(Primary Standard Industrial Classification Code Number, if applicable)

Not Applicable
(I.R.S. Employer Identification Number, if applicable)

2600, 500 Centre Street S.E.
Calgary, Alberta, Canada T2G 1A6
(403) 766-2000
(Address and telephone number of Registrant's principal executive offices)

CT Corporation System
111 8^th Avenue
New York, New York 10011
(212) 894-8641
(Name, address (including zip code) and telephone number (including area code) of agent for service in the United States)

	Copies to:
Kerry D. Dyte Cenovus Energy Inc. 2600, 500 Centre Street S.E. Calgary, Alberta, Canada T2G 1A6 (403) 766-2000	Andrew J. Foley Paul, Weiss, Rifkind, Wharton & Garrison LLP 1285 Avenue of the Americas New York, N.Y. 10019-6064 (212) 373-3000	Don Tse Norton Rose Fulbright Canada LLP 400 3rd Avenue SW, Suite 3700 Calgary, Alberta Canada T2P 4H2 (403) 267-8249

Approximate date of commencement of proposed sale to the public:
From time to time after the effective date of this Registration Statement.

Province of Alberta, Canada
(Principal jurisdiction regulating this offering)

It is proposed that this filing shall become effective (check appropriate box):

A.	o	Upon filing with the Commission, pursuant to Rule 467(a) (if in connection with an offering being made contemporaneously in the United States and Canada).
B.	ý	At some future date (check appropriate box below):
	1.	o	pursuant to Rule 467(b) on (  ) at (  ) (designate a time not sooner than 7 calendar days after filing).
	2.	o	pursuant to Rule 467(b) on (  ) at (  ) (designate a time 7 calendar days or sooner after filing) because the securities regulatory authority in the review jurisdiction has issued a receipt or notification of clearance on (  ).
	3.	o	pursuant to Rule 467(b) as soon as practicable after notification of the Commission by the Registrant or the Canadian securities regulatory authority of the review jurisdiction that a receipt or notification of clearance has been issued with respect hereto.
	4.	ý	after the filing of the next amendment to this Form (if preliminary material is being filed).

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to the home jurisdiction's shelf prospectus offering procedures, check the following box.    ý

CALCULATION OF REGISTRATION FEE

Title of each class of securities to be registered	Amount to be registered(1)(3)	Proposed maximum offering price per unit(2)	Proposed maximum aggregate offering price(2)(3)	Amount of registration fee(3)
Debt Securities	U.S.$800,000,000	100%	U.S.$800,000,000	U.S.$103,040

(1)

The proposed maximum initial offering price per debt security will be determined, from time to time, by the Registrant in connection with the sale of the debt securities under this Registration Statement.

(2)

Estimated solely for the purpose of determining the registration fee pursuant to Rule 457(o) of the Securities Act of 1933, as amended.

(3)

The prospectus contained herein relates to an aggregate of U.S.$2,000,000,000 of debt securities, including, pursuant to Rule 429 under the Securities Act of 1933, as amended, U.S.$1,200,000,000 of unsold debt securities that were previously registered under the Registrant's Registration Statement on Form F-10 (File No. 333-188478), initially filed on May 9, 2013.

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registration Statement shall become effective as provided in Rule 467 under the Securities Act of 1933, as amended, or on such date as the Commission, acting pursuant to Section 8(a) of the Act, may determine.

Pursuant to Rule 429 under the Securities Act of 1933, as amended, the prospectus contained in this Registration Statement relates to Registration Statement 333-188478.

PART I

INFORMATION REQUIRED TO BE DELIVERED
TO OFFEREES OR PURCHASERS

Subject to completion, dated June 12, 2014

Information contained herein is subject to completion or amendment. A registration statement relating to these securities has been filed with the Securities and Exchange Commission. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. This prospectus shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any State in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such State.

New Issue Preliminary Short Form Base Shelf Prospectus Dated June 12, 2014

Cenovus Energy Inc.

US$2,000,000,000

Debt Securities

We may from time to time offer and sell up to US$2,000,000,000 (or the equivalent in other currencies) aggregate principal amount of our debt securities. These debt securities may be offered and sold in the United States and elsewhere where permitted by law. These debt securities may consist of debentures, notes or other types of debt and may be issuable in series. We will provide the specific terms of these securities in supplements to this prospectus that will be delivered to purchasers together with this prospectus. Unless otherwise provided in a prospectus supplement relating to a series of debt securities, the debt securities will be our direct, unsecured and unsubordinated obligations and will be issued under a trust indenture. You should read this prospectus and any prospectus supplement carefully before you invest.

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

We are permitted, under a multijurisdictional disclosure system adopted by the United States, to prepare this prospectus in accordance with Canadian disclosure requirements, which are different from those of the United States. We prepare our financial statements in accordance with International Financial Reporting Standards as issued by the International Accounting Standards Board ("IFRS") and they are subject to Canadian auditing and auditor independence standards. They may not be comparable to financial statements of United States companies.

Owning the debt securities may subject you to tax consequences both in the United States and Canada. This prospectus or any applicable prospectus supplement may not describe these tax consequences fully. You should read the tax discussion in any applicable prospectus supplement.

Your ability to enforce civil liabilities under the United States federal securities laws may be affected adversely because we are incorporated in Canada, most of our officers and directors and some of the experts named in this prospectus are Canadian residents, and most of our assets and the assets of our directors and officers and the experts are located outside the United States.

There is no market through which these securities may be sold and purchasers may not be able to resell securities purchased under this prospectus. This may affect the pricing of the securities in the secondary market, the transparency and availability of trading prices, the liquidity of the securities, and the extent of issuer regulation. See "Risk Factors".

Our registered and principal office is located at 2600, 500 Centre Street S.E., Calgary, Alberta, Canada T2G 1A6.

                         , 2014

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS	2
WHERE YOU CAN FIND MORE INFORMATION	3
FORWARD-LOOKING STATEMENTS	6
CENOVUS ENERGY INC.	9
USE OF PROCEEDS	9
DESCRIPTION OF DEBT SECURITIES	10
RISK FACTORS	29
CERTAIN INCOME TAX CONSIDERATIONS	31
PLAN OF DISTRIBUTION	31
INTEREST COVERAGE	32
LEGAL MATTERS	33
EXPERTS	33
AGENT FOR SERVICE OF PROCESS IN CANADA	34
ENFORCEABILITY OF CIVIL LIABILITIES	34
DOCUMENTS FILED AS PART OF THE REGISTRATION STATEMENT	35

ABOUT THIS PROSPECTUS

        Except as set forth under "Description of Debt Securities", and unless the context otherwise requires, all references in this prospectus and any prospectus supplement to "Cenovus", "we", "us" and "our" mean Cenovus Energy Inc. and its consolidated subsidiaries and partnerships.

        In this prospectus, in any prospectus supplement and in documents incorporated by reference in this prospectus, unless otherwise specified or the context otherwise requires, all dollar amounts are expressed in Canadian dollars, references to "dollars", or "$" are to Canadian dollars and all references to "US$" are to U.S. dollars. Unless otherwise indicated, all financial information included and incorporated by reference in this prospectus or included in any prospectus supplement is determined using IFRS, which have been adopted as Canadian generally accepted accounting principles, referred to as "Canadian GAAP".

        We may, from time to time, sell any combination of the debt securities described in this prospectus in one or more offerings up to an aggregate principal amount of US$2,000,000,000. This prospectus provides you with a general description of the debt securities that we may offer. Each time we sell debt securities under this prospectus, we will provide a prospectus supplement that will contain specific information about the terms of that offering of debt securities. The prospectus supplement may also add, update or change information contained in this prospectus. Before you invest, you should read both this prospectus and any applicable prospectus supplement together with additional information described under the heading "Where You Can Find More Information". This prospectus does not contain all of the information set forth in the registration statement, certain parts of which are omitted in accordance with the rules and regulations of the United States Securities and Exchange Commission (the "SEC"). You may refer to the registration statement and the exhibits to the registration statement for further information with respect to us and the debt securities.

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WHERE YOU CAN FIND MORE INFORMATION

Information has been incorporated by reference in this prospectus from documents filed with securities commissions or similar authorities in Canada. Copies of the documents incorporated by reference herein may be obtained on request without charge from the Corporate Secretary of Cenovus Energy Inc., 2600, 500 Centre Street S.E., Calgary, Alberta, Canada T2G 1A6, telephone (403) 766-2000. These documents are also available through the internet via the System for Electronic Document Analysis and Retrieval (SEDAR), which can be accessed at www.sedar.com.

        We file with the securities commission or authority in each of the provinces and territories of Canada, annual and quarterly reports, material change reports and other information. We are subject to the informational requirements of the United States Securities Exchange Act of 1934, as amended (the "Exchange Act"), and, in accordance with the Exchange Act, we also file reports with and furnish other information to the SEC. Under the multijurisdictional disclosure system adopted by the United States, these reports and other information (including financial information) may be prepared, in part, in accordance with the disclosure requirements of Canada, which differ from those in the United States. You may read any document we furnish to the SEC at the SEC's public reference room at Room 1580, 100 F Street, N.E., Washington, D.C. 20549. You may also obtain copies of the same documents from the public reference room of the SEC at 100 F Street, N.E., Washington D.C. 20549 by paying a fee. Please call the SEC at 1-800-SEC-0330 or contact them at www.sec.gov for further information on the public reference rooms. Our filings are also electronically available from the SEC's Electronic Document Gathering, Analysis and Retrieval system (EDGAR), which can be accessed at www.sec.gov, as well as from commercial document retrieval services.

        Under applicable securities laws in Canada and the United States, the Canadian securities commissions and the SEC allow us to incorporate by reference certain information that we file with them, which means that we can disclose important information to you by referring you to those documents. Information that is incorporated by reference is an important part of this prospectus. We incorporate by reference the documents listed below, which were filed with the Canadian securities commissions under Canadian securities legislation:

(a)

our audited annual consolidated financial statements and auditor's report thereon for the year ended December 31, 2013;



(b)

our Management's Discussion and Analysis for the year ended December 31, 2013;



(c)

our Annual Information Form dated February 12, 2014;



(d)

our Management Proxy Circular dated March 7, 2014 in connection with an annual meeting of shareholders held on April 30, 2014;



(e)

our unaudited interim consolidated financial statements for the period ended March 31, 2014; and



(f)

our Management's Discussion and Analysis for the three months ended March 31, 2014.

Any annual information form, audited annual consolidated financial statements (together with the auditor's report thereon), information circular, unaudited interim consolidated

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financial statements, management's discussion and analysis, material change reports (excluding confidential material change reports) or business acquisition reports subsequently filed by us with securities commissions or similar authorities in the relevant provinces and territories of Canada after the date of this prospectus and prior to the termination of the offering of debt securities under any prospectus supplement shall be deemed to be incorporated by reference into this prospectus. These documents are available through the internet on SEDAR. In addition, any similar documents filed by us with the SEC in our periodic reports on Form 6-K or annual reports on Form 40-F and any other documents filed with or furnished to the SEC pursuant to Section 13(a), 13(c) or 15(d) of the Exchange Act, in each case after the date of this prospectus, shall be deemed to be incorporated by reference into this prospectus and the registration statement of which this prospectus forms a part. To the extent that any document or information incorporated by reference into this prospectus is included in a report that is filed with or furnished to the SEC on Form 40-F, 20-F, 10-K, 10-Q, 8-K or 6-K (or any respective successor form), such document or information shall also be deemed to be incorporated by reference as an exhibit to the registration statement of which this prospectus forms a part.

Any statement contained in this prospectus or in a document (or part thereof) incorporated by reference, or deemed to be incorporated by reference, in this prospectus shall be deemed to be modified or superseded, for purposes of this prospectus, to the extent that a statement contained in the prospectus or in any subsequently filed document (or part thereof) that also is, or is deemed to be, incorporated by reference in this prospectus modifies or replaces such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute part of this prospectus. The modifying or superseding statement need not state that it has modified or superseded a prior statement or include any other information set forth in the document which it modifies or supersedes.

Any "template version" of "marketing materials" (as those terms are defined under applicable Canadian securities laws) that are utilized in connection with the distribution of debt securities will be filed on SEDAR. In the event that such marketing materials are filed after the date of the applicable prospectus supplement for the offering and before termination of the distribution of such debt securities, such filed versions of the marketing materials will be deemed to be incorporated by reference into the applicable prospectus supplement for the purposes of the distribution of the debt securities to which the prospectus supplement pertains.

        We will file updated interest coverage ratios quarterly with the applicable securities regulatory authorities, including the SEC, either as prospectus supplements or exhibits to our unaudited interim consolidated financial statements and audited annual consolidated financial statements which will be deemed to be incorporated by reference in this prospectus for the purpose of the offering of the debt securities.

        Upon a new annual information form and related audited annual consolidated financial statements and management's discussion and analysis being filed by us with the applicable securities regulatory authorities during the duration of this prospectus, the previous annual information form, the previous audited annual consolidated financial statements and all interim consolidated financial statements and the accompanying management's discussion and analysis and material change reports filed prior to the commencement of our financial year in which the new annual information form is filed shall be deemed no longer to be incorporated into this prospectus for purposes of future offers and sales of debt securities under this prospectus. Upon interim consolidated financial statements and the accompanying

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management's discussion and analysis being filed by us with the applicable securities regulatory authorities during the duration of this prospectus, all interim consolidated financial statements and the accompanying management's discussion and analysis filed prior to the new interim consolidated financial statements shall be deemed no longer to be incorporated into this prospectus for purposes of future offers and sales of debt securities under this prospectus. Upon a new information circular in connection with an annual meeting being filed by us with the applicable securities regulatory authorities during the duration of this prospectus, the previous information circular filed in connection with an annual meeting shall be deemed no longer to be incorporated into this prospectus for purposes of future offers and sales of debt securities under this prospectus.

        A prospectus supplement or prospectus supplements containing the specific terms for an issue of debt securities will be delivered to purchasers of such debt securities together with this prospectus and will be deemed to be incorporated by reference into this prospectus as of the date of such prospectus supplement but only for the purposes of the debt securities issued thereunder.

        You may obtain a copy of our Annual Information Form and other information identified above by writing or calling us at the following address or telephone number:

Cenovus Energy Inc.
2600, 500 Centre Street S.E.
Calgary, Alberta T2G 1A6
Attention: Investor Relations
(403) 766-2000

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FORWARD-LOOKING STATEMENTS

        This prospectus and the documents incorporated by reference in this prospectus contain certain forward-looking statements and information (collectively referred to as "forward-looking statements") within the meaning of applicable securities legislation, including the United States Private Securities Litigation Reform Act of 1995, about our current expectations, estimates and projections about the future, based on certain assumptions made by us in light of our experience and perception of historical trends. Although we believe that the expectations represented by such forward-looking statements are reasonable, there can be no assurance that such expectations will prove to be correct.

        These forward-looking statements are identified by words such as "anticipate", "believe", "expect", "plan", "forecast" or "F", "target", "projected", "could", "focus", "proposed", "schedule", "outlook", "potential", "may", "strategy" or similar expressions and includes suggestions of future outcomes, including statements about our growth strategy and related schedules, projections contained in our current guidance, projected future value, forecast operating and financial results, planned capital expenditures, expected future production, including the timing, stability or growth thereof, expected future refining capacity, broadening market access, improving cost structures, expected reserves and contingent and prospective resources estimates, potential dividends and dividend growth strategy, anticipated timelines for future regulatory, partner or internal approvals, future impact of regulatory measures, forecasted commodity prices, future use and development of technology and projected increasing shareholder value. You are cautioned not to place undue reliance on forward-looking statements as our actual results may differ materially from those expressed or implied.

        Developing forward-looking statements involves reliance on a number of assumptions and consideration of certain risks and uncertainties, some of which are specific to us and others that apply to the industry generally. The factors or assumptions on which the forward-looking statements are based include: assumptions disclosed in our current guidance, available at cenovus.com; our projected capital investment levels, the flexibility of our capital spending plans and the associated source of funding; estimates of quantities of oil, bitumen, natural gas and liquids from properties and other sources not currently classified as proved; our ability to obtain necessary regulatory and partner approvals; the successful and timely implementation of capital projects or stages thereof; our ability to generate sufficient cash flow from operations to meet our current and future obligations; and other risks and uncertainties described from time to time in the filings we make with securities regulatory authorities.

        The information contained on our website is not incorporated into this prospectus. The reference to our website is intended to be an inactive textual reference.

        Forward-looking statements involve a number of risks and uncertainties, some of which are specific to us and others that apply to the industry generally. The risk factors and uncertainties that could cause actual results to differ materially include, among other things:

•

volatility of and assumptions regarding oil and gas prices;

•

the effectiveness of our risk management program, including the impact of derivative financial instruments and the success of our hedging strategies;

•

the accuracy of cost estimates;

•

fluctuations in commodity prices, currency and interest rates;

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•

fluctuations in product supply and demand; market competition, including from alternative energy sources;

•

risks inherent in our marketing operations, including credit risks;

•

maintaining desirable ratios of debt to adjusted earnings before interest, taxes, depreciation and amortization as well as debt to capitalization;

•

our ability to access various sources of debt and equity capital;

•

accuracy of our reserves, resources and future production estimates;

•

our ability to replace and expand oil and gas reserves;

•

our ability to maintain our relationships with our partners and to successfully manage and operate our integrated heavy oil business;

•

reliability of our assets;

•

potential disruption or unexpected technical difficulties in developing new products and manufacturing processes;

•

refining and marketing margins;

•

potential failure of new products to achieve acceptance in the market;

•

unexpected cost increases or technical difficulties in constructing or modifying manufacturing or refining facilities;

•

unexpected difficulties in producing, transporting or refining of crude oil into petroleum and chemical products;

•

risks associated with technology and its application to our business;

•

the timing and the costs of well and pipeline construction;

•

our ability to secure adequate product transportation, including sufficient crude-by-rail or other alternate transportation;

•

changes in the regulatory framework in any of the locations in which we operate, including changes to the regulatory approval process and land-use designations, royalty, tax, environmental, greenhouse gas, carbon and other laws or regulations, or changes to the interpretation of such laws and regulations, as adopted or proposed, the impact thereof and the costs associated with compliance;

•

the expected impact and timing of various accounting pronouncements, rule changes and standards on our business, our financial results and our consolidated financial statements; changes in the general economic, market and business conditions;

•

the political and economic conditions in the countries in which we operate;

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•

the occurrence of unexpected events such as war, terrorist threats and the instability resulting therefrom; and

•

risks associated with existing and potential future lawsuits and regulatory actions against us.

        Statements relating to "reserves" and "contingent resources" are deemed to be forward-looking statements, as they involve the implied assessment, based on certain estimates and assumptions, that the reserves and contingent resources described exist in the quantities predicted or estimated, and can be profitably produced in the future.

        We caution that the foregoing list of important factors is not exhaustive. Events or circumstances could cause our actual results to differ materially from those estimated or projected and expressed in, or implied by, these forward-looking statements. You should carefully consider the matters discussed under "Risk Factors" in this prospectus and in any applicable prospectus supplement. You should also refer to "Risk Management" in our annual Management's Discussion and Analysis incorporated by reference herein and to the risk factors described in other documents incorporated by reference herein we file from time to time with securities regulatory authorities, available at www.sedar.com, www.sec.gov and on our website at cenovus.com. Except as required by applicable securities law, we undertake no obligation to update publicly or otherwise revise any forward-looking statements or the foregoing list of factors affecting those statements, whether as a result of new information, future events or otherwise. Information on or connected to our website, even if referred to in a document incorporated by reference herein, does not constitute part of this prospectus.

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CENOVUS ENERGY INC.

        Cenovus is a Canadian integrated oil company headquartered in Calgary, Alberta. We are in the business of developing, producing and marketing crude oil, natural gas liquids ("NGLs") and natural gas in Canada with refining operations in two refineries in the U.S. in Illinois and Texas.

        We began independent operations on December 1, 2009 following the split of Encana Corporation ("Encana") into two independent publicly traded energy companies, Cenovus and Encana.

        Our reportable segments are as follows:

•

Oil Sands, which includes the development and production of Cenovus's bitumen assets at Foster Creek, Christina Lake and Narrows Lake as well as projects in the early stages of development, such as Grand Rapids and Telephone Lake. The Athabasca natural gas assets also form part of this segment. Certain of the Company's operated oil sands properties, notably Foster Creek, Christina Lake and Narrows Lake, are jointly owned with ConocoPhillips, an unrelated U.S. public company.

•

Conventional, which includes the development and production of conventional crude oil, NGLs and natural gas in Alberta and Saskatchewan, including the heavy oil assets at Pelican Lake. This segment also includes the carbon dioxide enhanced oil recovery project at Weyburn and emerging tight oil opportunities.

•

Refining and Marketing, which is focused on the refining of crude oil products into petroleum and chemical products at two refineries located in the U.S. The refineries are jointly owned with and operated by Phillips 66, an unrelated U.S. public company. This segment also markets Cenovus's crude oil and natural gas, as well as third-party purchases and sales of product that provide operational flexibility for transportation commitments, product type, delivery points and customer diversification.

•

Corporate and Eliminations, which primarily includes unrealized gains and losses recorded on derivative financial instruments, gains and losses on divestiture of assets, as well as other Cenovus-wide costs for general and administrative, research costs and financing activities. As financial instruments are settled, the realized gains and losses are recorded in the operating segment to which the derivative instrument relates. Eliminations relate to sales and operating revenues and purchased product between segments, recorded at transfer prices based on current market prices, and to unrealized intersegment profits in inventory.

USE OF PROCEEDS

        Unless otherwise indicated in the applicable prospectus supplement relating to a series of debt securities, we will use the net proceeds we receive from the sale of the debt securities for general corporate purposes. Those general corporate purposes may include capital expenditures, the repayment of indebtedness and the financing of acquisitions. We may invest funds that we do not immediately use in short-term marketable securities. The amount of net proceeds to be used for any such purpose will be described in an applicable prospectus supplement.

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DESCRIPTION OF DEBT SECURITIES

        In this section only, "we", "us", "our" or "Cenovus" refer only to Cenovus Energy Inc. without any of its subsidiaries or partnerships through which it operates. The following description describes certain general terms and provisions of the debt securities. We will provide the particular terms and provisions of a series of debt securities and a description of how the general terms and provisions described below may apply to that series in a supplement to this prospectus.

        The debt securities will be issued under an indenture (the "Indenture") entered into between us and The Bank of New York Mellon, as "Trustee", dated August 17, 2012. The Indenture is subject to and governed by the U.S. Trust Indenture Act of 1939, as amended. The following is a summary of the Indenture which describes the material terms and provisions of the debt securities. However, it is the Indenture, and not this summary, that governs your rights as a holder of our debt securities. The Indenture has been filed with the SEC and is available on EDGAR. See "Where You Can Find More Information" in this prospectus. In addition, prospective investors should rely on information in the applicable prospectus supplement, which may provide information that is different from this prospectus.

        We may, from time to time, issue debt instruments and incur additional indebtedness other than through the issuance of debt securities pursuant to this prospectus.

General

        The Indenture does not limit the aggregate principal amount of debt securities (which may include debentures, notes and other unsecured evidences of indebtedness) that we may issue under the Indenture. It provides that debt securities may be issued from time to time in one or more series and may be denominated and payable in U.S. dollars or any foreign currency. Special Canadian and U.S. federal income tax considerations applicable to any of our debt securities denominated in a currency other than U.S. dollars will be described in the applicable prospectus supplement. The debt securities offered pursuant to this prospectus will be issued in an aggregate principal amount of up to US$2,000,000,000, or if any debt securities are offered at an original issue discount, such greater amount as shall result in an aggregate offering price of up to US$2,000,000,000, or the equivalent in other currencies. The Indenture also permits us to increase the principal amount of any series of our debt securities previously issued and to issue debt securities of that increased principal amount. The applicable prospectus supplement will set forth the following terms and information relating to the debt securities being offered by us:

•

the specific designation and the aggregate principal amount of the debt securities of such series;

•

the extent and manner, if any, to which payment on or in respect of our debt securities of such series will be senior or will be subordinated to the prior payment of our other liabilities and obligations;

•

the percentage or percentages of principal amount at which our debt securities of such series will be issued;

•

the date or dates on which the principal of (and premium, if any, on) our debt securities of such series will be payable and the portion (if less than the principal amount) of the debt securities of such series to be payable upon a

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declaration of acceleration of maturity and/or the method by which such date or dates shall be determined or extended;

•

the rate or rates (whether fixed or variable) at which our debt securities of such series will bear interest, if any, and the date or dates from which such interest will accrue;

•

the dates on which any interest will be payable and the regular record dates for the payment of interest on our debt securities of such series in registered form;

•

the place or places where the principal of (and premium, if any, and interest, if any, on) our debt securities will be payable, and each office or agency where our debt securities of such series may be presented for registration of transfer or exchange;

•

if other than U.S. dollars, the currency in which our debt securities of such series are denominated or in which currency payment of the principal of (and premium, if any, and interest, if any, on) such debt securities of such series will be payable;

•

whether our debt securities of such series will be issuable in the form of one or more global securities and, if so, the identity of the depositary for the global securities;

•

any mandatory or optional redemption or sinking fund provisions;

•

the period or periods, if any, within which, the price or prices at which, the currency in which and the terms and conditions upon which our debt securities of such series may be redeemed or purchased by us;

•

the terms and conditions, if any, upon which you may redeem our debt securities of such series prior to maturity and the price or prices at which and the currency in which our debt securities of such series are payable;

•

any index used to determine the amount of payments of principal of (and premium, if any, or interest, if any, on) our debt securities of such series;

•

the terms, if any, on which our debt securities may be converted or exchanged for other of our debt securities or debt securities of other entities;

•

any other terms of our debt securities of such series, including covenants and events of default which apply solely to a particular series of our debt securities being offered which do not apply generally to other debt securities, or any covenants or events of default generally applicable to our debt securities of such series which do not apply to a particular series of our debt securities;

•

if other than The Depository Trust Company, the person designated as the depositary for the debt securities of such series;

•

any applicable material Canadian and U.S. federal income tax consequences;

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•

whether and under what circumstances we will pay Additional Amounts (defined below under "Payment of Additional Amounts") on the debt securities of such series in respect of certain taxes (and the terms of any such payment) and, if so, whether we will have the option to redeem the debt securities of such series rather than pay the Additional Amounts (and the terms of any such option);

•

whether the payment of our debt securities will be guaranteed by any other person; and

•

if other than denominations of US$2,000 and any integral multiple of US$1,000 in excess thereof, the denominations in which any securities of the series shall be issuable.

        Unless otherwise indicated in the applicable prospectus supplement, the Indenture does not afford holders of our debt securities the right to tender such debt securities to us in the event that we have a change in control.

        Our debt securities may be issued under the Indenture bearing no interest or at a discount below their stated principal amount. The Canadian and U.S. federal income tax consequences and other special considerations applicable to any such discounted debt securities or other debt securities offered and sold at par which are treated as having been issued at a discount for Canadian and/or U.S. federal income tax purposes will be described in the prospectus supplement relating to the debt securities.

Ranking

        Unless otherwise indicated in an applicable prospectus supplement, the debt securities issued under the Indenture will be unsecured and unsubordinated obligations and will rank equally with all of our other unsecured and unsubordinated indebtedness outstanding from time to time. We conduct a substantial portion of our business through corporate and partnership subsidiaries. The debt securities will be structurally subordinated to all existing and future indebtedness and liabilities, including trade payables, of any of our corporate or partnership subsidiaries. See "Risk Factors".

Debt Securities in Global Form

The Depositary, Book-Entry and Settlement

        A series of our debt securities may be issued in whole or in part in global form as a "global security" and will be registered in the name of and be deposited with a depositary, or its nominee, each of which will be identified in the prospectus supplement relating to that series. Unless and until exchanged, in whole or in part, for our debt securities in definitive registered form, a global security may not be transferred except as a whole by the depositary for such global security to a nominee of the depositary, by a nominee of the depositary to the depositary or another nominee of the depositary or by the depositary or any such nominee to a successor of the depositary or a nominee of the successor.

        The specific terms of the depositary arrangement with respect to any portion of a particular series of our debt securities to be represented by a global security will be described in a prospectus supplement relating to such series. We anticipate that the following provisions will apply to all depositary arrangements.

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        Upon the issuance of a global security, the depositary therefor or its nominee will credit, on its book entry and registration system, the respective principal amounts of our debt securities represented by the global security to the accounts of such persons, designated as "participants", having accounts with such depositary or its nominee. Such accounts shall be designated by the underwriters, dealers or agents participating in the distribution of our debt securities or by us if such debt securities are offered and sold directly by us. Ownership of beneficial interests in a global security will be limited to participants or persons that may hold beneficial interests through participants. Ownership of beneficial interests in a global security will be shown on, and the transfer of that ownership will be effected only through, records maintained by the depositary therefor or its nominee (with respect to interests of participants) or by participants or persons that hold through participants (with respect to interests of persons other than participants). The laws of some states in the United States may require that certain purchasers of securities have the ability to take physical delivery of such securities in definitive form.

        So long as the depositary for a global security, or its nominee, is the registered owner of the global security, such depositary or such nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by the global security for all purposes under the Indenture. Except as provided below, owners of beneficial interests in a global security will not be entitled to have a series of our debt securities represented by the global security registered in their names and will not receive or be entitled to receive physical delivery of such series of our debt securities in definitive form.

Payments of Principal, Premium, if any, and Interest

        Any payments of principal, premium, if any, and interest on global securities registered in the name of a depositary or its nominee will be made to the depositary or its nominee, as the case may be, as the registered owner of the global security representing such debt securities. None of us, the Trustee or any paying agent for our debt securities represented by the global securities will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests of the global security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

        We expect that the depositary for a global security or its nominee, upon receipt of any payment of principal, premium, if any, or interest, will credit participants' accounts with payments in amounts proportionate to their respective beneficial interests in the principal amount of the global security as shown on the records of such depositary or its nominee. We also expect that payments by participants to owners of beneficial interests in a global security held through such participants will be governed by standing instructions and customary practices, as is now the case with securities held for the accounts of customers registered in "street name", and will be the responsibility of such participants.

Discontinuance of Depositary's Services

        If a depositary for a global security representing a particular series of our debt securities is at any time unwilling or unable to continue as depositary and a successor depositary is not appointed by us within 90 days, we will issue such series of our debt securities in definitive form in exchange for a global security representing such series of our debt securities. In addition, we may at any time and in our sole discretion determine not to have a series of our debt securities represented by a global security and, in such event, will issue a series of our debt securities in definitive form in exchange for the global security representing such series of debt securities.

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Debt Securities in Definitive Form

        A series of our debt securities may be issued solely as registered securities in denominations of US$2,000 and any integral multiple of US$1,000 in excess thereof or in such other denominations as may be set out in a prospectus supplement relating to any particular series.

        An applicable prospectus supplement will indicate the places to register a transfer of our debt securities in definitive form. Except for certain restrictions set forth in the Indenture, no service charge will be made for any registration of transfer or exchange of such debt securities, but we may, in certain instances, require a sum sufficient to cover any tax or other governmental charges payable in connection with these transactions.

        We shall not be required to:

•

issue, register the transfer of or exchange any series of our debt securities during a period beginning at the opening of business 15 days before the day of the selection for redemption of debt securities of that series to be redeemed and ending at the close of business on the day of mailing of the relevant notice of redemption;

•

register the transfer of or exchange any debt security, or portion thereof, called for redemption, except the unredeemed portion of any debt security being redeemed in part; or

•

issue, register the transfer of or exchange any of our debt securities which have been surrendered for repayment at the option of the holder, except the portion, if any, thereof not to be so repaid.

        Unless otherwise indicated in the applicable prospectus supplement, payment of any interest will be made to the persons in whose name our debt securities are registered at the close of business on the day or days specified by us.

Certain Definitions

        Set forth below is a summary of certain of the defined terms used in the Indenture. The Indenture contains the full definition of all such terms. See "Where You Can Find More Information" in this prospectus.

"Consolidated Net Tangible Assets" means the total amount of assets of any person on a consolidated basis (less applicable reserves and other properly deductible items) after deducting therefrom:

•

all current liabilities (excluding any indebtedness classified as a current liability and any current liabilities which are by their terms extendible or renewable at the option of the obligor thereon to a time more than 12 months after the time as of which the amount thereof is being computed and excluding any liabilities related to assets held for sale);

•

all goodwill, trade names, trademarks, patents and other like intangibles; and

•

appropriate adjustments on account of non-controlling interests of other persons holding shares of the Subsidiaries of such person,

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in each case, as shown on the most recent annual audited or quarterly unaudited consolidated balance sheet of such person computed in accordance with GAAP.

"Current Assets" means assets which in the ordinary course of business are expected to be realized in cash or sold or consumed within 12 months.

"Facilities" means any drilling equipment, production equipment and platforms or mining equipment; pipelines, pumping stations and other pipeline facilities; terminals, warehouses and storage facilities; refineries and related facilities; bulk plants; production, separation, dehydration, extraction, treating and processing facilities; gasification or natural gas liquefying facilities, flares, stacks and burning towers; floatation mills, crushers and ore handling facilities; tank cars, tankers, barges, ships, trucks, automobiles, airplanes and other marine, automotive, aeronautical and other similar moveable facilities or equipment; computer systems and associated programs or office equipment; roads, airports, docks (including drydocks); reservoirs and waste disposal facilities; sewers; generating plants (including power plants) and electric lines; telephone and telegraph lines, radio and other communications facilities; townsites, housing facilities, recreation halls, stores and other related facilities; and similar facilities and equipment of or associated with any of the foregoing.

"Financial Instrument Obligations" means obligations arising under:

•

interest rate swap agreements, forward rate agreements, floor, cap or collar agreements, futures or options, insurance or other similar agreements or arrangements, or any combination thereof, entered into by a person relating to interest rates or pursuant to which the price, value or amount payable thereunder is dependent or based upon interest rates in effect from time to time or fluctuations in interest rates occurring from time to time;

•

currency swap agreements, cross-currency agreements, forward agreements, floor, cap or collar agreements, futures or options, insurance or other similar agreements or arrangements, or any combination thereof, entered into by a person relating to currency exchange rates or pursuant to which the price, value or amount payable thereunder is dependent or based upon currency exchange rates in effect from time to time or fluctuations in currency exchange rates occurring from time to time; and

•

commodity swap or hedging agreements, floor, cap or collar agreements, commodity futures or options or other similar agreements or arrangements, or any combination thereof, entered into by a person relating to one or more commodities or pursuant to which the price, value or amount payable thereunder is dependent or based upon the price of one or more commodities in effect from time to time or fluctuations in the price of one or more commodities occurring from time to time.

"GAAP" means generally accepted accounting principles in Canada which are in effect from time to time (including, for clarity and as applicable, International Financial Reporting Standards as issued by the International Accounting Standards Board), unless the person's most recent audited or quarterly financial statements are not prepared in accordance with generally accepted accounting principles in Canada, in which case GAAP shall mean generally accepted accounting principles in the United States in effect from time to time.

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"Lien" means, with respect to any properties or assets, any mortgage or deed of trust, pledge, hypothecation, assignment, security interest, lien, charge, encumbrance, preference, priority or other security agreement or preferential arrangement of any kind or nature whatsoever on or with respect to such properties or assets (including, without limitation, any conditional sale or other title retention agreement having substantially the same economic effect as any of the foregoing).

"Non-Recourse Debt" means indebtedness to finance the creation, development, construction or acquisition of properties or assets and any increases in or extensions, renewals or refinancings of such indebtedness, provided that the recourse of the lender thereof (including any agent, trustee, receiver or other person acting on behalf of such lender) in respect of such indebtedness is limited in all circumstances to the properties or assets created, developed, constructed or acquired in respect of which such indebtedness has been incurred and to the receivables, inventory, equipment, chattels payable, contracts, intangibles and other assets, rights or collateral connected with the properties or assets created, developed, constructed or acquired and to which such lender has recourse.

"Permitted Liens" of any person at any particular time means:

•

Liens existing as of the date of the Indenture, or arising thereafter pursuant to contractual commitments entered into prior to such date;

•

Liens on Current Assets given in the ordinary course of business to any financial institution or others to secure any indebtedness payable on demand or maturing (including any right of extension or renewal) within 12 months or less from the date such indebtedness is incurred;

•

Liens in connection with indebtedness, which, by its terms, is Non-Recourse Debt to us or any of our Subsidiaries;

•

Liens existing on property or assets at the time of acquisition (including by way of lease) by such person, provided that such Liens were not incurred in anticipation of such acquisition;

•

Liens or obligations to incur Liens (including under indentures, trust deeds and similar instruments) on property or assets of another person existing at the time such other person becomes a Subsidiary of such person, or is liquidated or merged into, or amalgamated or consolidated with, such person or Subsidiary of such person or at the time of the sale, lease or other disposition to such person or Subsidiary of such person of all or substantially all of the properties and assets of such other person, provided that such Liens were not incurred in anticipation of such other person becoming a Subsidiary of such person;

•

Liens upon property or assets of whatsoever nature other than Restricted Property;

•

Liens upon property or facilities used in connection with, or necessarily incidental to, the purchase, sale, storage, transportation or distribution of oil or gas, or the products derived from oil or gas;

•

Liens arising under partnership agreements, oil and natural gas leases, overriding royalty agreements, net profits agreements, production payment agreements, royalty trust agreements, master limited partnership

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agreements, farm-out agreements, division orders, contracts for the sale, purchase, exchange, storage, transportation, distribution, gathering or processing of Restricted Property, unitizations and pooling designations, declarations, orders and agreements, development agreements, operating agreements, production sales contracts (including security in respect of take or pay or similar obligations thereunder), area of mutual interest agreements, natural gas balancing or deferred production agreements, injection, repressuring and recycling agreements, salt water or other disposal agreements, seismic or geophysical permits or agreements, which in each of the foregoing cases is customary in the oil and natural gas business, and other agreements which are customary in the oil and natural gas business, provided in all instances that such Lien is limited to the property or assets that are the subject of the relevant agreement;

•

Liens on assets or property (including oil sands property) securing: (i) all or any portion of the cost of acquisition (directly or indirectly), surveying, exploration, drilling, development, extraction, operation, production, construction, alteration, repair or improvement of all or any part of such assets or property, the plugging and abandonment of wells and the decommissioning or removal of structures or facilities located thereon, and the reclamation and clean-up of such properties, facilities and interests and surrounding lands whether or not owned by us or our Restricted Subsidiaries, (ii) all or any portion of the cost of acquiring (directly or indirectly), developing, constructing, altering, improving, operating or repairing any assets or property (or improvements on such assets or property) used or to be used in connection with such assets or property, whether or not located (or located from time to time) at or on such assets or property, (iii) indebtedness incurred by us or any of our Subsidiaries to provide funds for the activities set forth in clauses (i) and (ii) above, provided such indebtedness is incurred prior to, during or within two years after the completion of acquisition, construction or such other activities referred to in clauses (i) and (ii) above, and (iv) indebtedness incurred by us or any of our Subsidiaries to refinance indebtedness incurred for the purposes set forth in clauses (i) and (ii) above. Without limiting the generality of the foregoing, costs incurred after the date hereof with respect to clauses (i) or (ii) above shall include costs incurred for all facilities relating to such assets or property, or to projects, ventures or other arrangements of which such assets or property form a part or which relate to such assets or property, which facilities shall include, without limitation, Facilities, whether or not in whole or in part located (or from time to time located) at or on such assets or property;

•

Liens granted in the ordinary course of business in connection with Financial Instrument Obligations;

•

Purchase Money Mortgages;

•

Liens in favor of us or any of our Subsidiaries to secure indebtedness owed to us or any of our Subsidiaries;

•

any Lien the validity of which is being contested at the time by us or any of our Subsidiaries in good faith or payment of which has been provided for by creation of a reserve in an amount in cash sufficient to pay the same in full; and

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•

any extension, renewal, alteration, refinancing, replacement, exchange or refunding (or successive extensions, renewals, alterations, refinancings, replacements, exchanges or refundings) of all or part of any Lien referred to in the foregoing clauses; provided, however, that (i) such new Lien shall be limited to all or part of the property or assets which was secured by the prior Lien plus improvements on such property or assets and (ii) the indebtedness, if any, secured by the new Lien is not increased from the amount of the indebtedness secured by the prior Lien then existing at the time of such extension, renewal, alteration, refinancing, replacement, exchange or refunding, plus an amount necessary to pay fees and expenses, including premiums, related to such extensions, renewals, alterations, refinancings, replacements, exchanges or refundings.

"Purchase Money Mortgage" of any person means any Lien created upon any property or assets of such person to secure or securing the whole or any part of the purchase price of such property or assets or the whole or any part of the cost of constructing or installing fixed improvements thereon or to secure or securing the repayment of money borrowed to pay the whole or any part of such purchase price or cost of any vendor's privilege or Lien on such property or assets securing all or any part of such purchase price or cost including title retention agreements and leases in the nature of title retention agreements; provided that (i) the principal amount of money borrowed which is secured by such Lien does not exceed 100% of such purchase price or cost and any fees incurred in connection therewith, and (ii) such Lien does not extend to or cover any other property other than such item of property and any improvements on such item.

"Restricted Property" means any oil, gas or mineral property of a primary nature located in the United States or Canada, and any facilities located in the United States or Canada directly related to the mining, processing or manufacture of hydrocarbons or minerals, or any of the constituents thereof or the derivatives therefrom and includes Voting Shares or other interests of a corporation or other person which owns such property or facilities, but does not include (i) any property or facilities used in connection with or necessarily incidental to the purchase, sale, storage, transportation or distribution of Restricted Property, (ii) any property which, in the opinion of our board of directors, is not materially important to the total business conducted by us and our Subsidiaries as an entirety, or (iii) any portion of a particular property which, in the opinion of our board of directors, is not materially important to the use or operation of such property.

"Restricted Subsidiary" means any Subsidiary of ours which owns Restricted Property which assets, calculated on a consolidated basis, represent not less than the greater of (i) 5% of our Consolidated Net Tangible Assets and (ii) $100,000,000 (or the equivalent thereof in any other currency), excluding however any Subsidiary of ours if the amount of our share of the Shareholders' Equity therein does not at the time exceed 2% of our Shareholders' Equity.

"Shareholders' Equity" means the aggregate amount of shareholders' equity (including but not limited to share capital, paid in surplus, accumulated other comprehensive income and retained earnings, but excluding non-controlling interests) of a person as shown on the most recent annual audited or unaudited interim consolidated balance sheet of such person and computed in accordance with GAAP.

"Subsidiary" of any person means, on any date, any corporation or other person of which Voting Shares or other interests carrying more than 50% of the voting rights attached to all outstanding Voting Shares or other interests are owned, directly or indirectly, by or for such person or one or more Subsidiaries thereof.

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"Voting Shares" means shares of any class of any corporation carrying voting rights under all circumstances, provided that, for the purposes of this definition, shares which only carry the right to vote conditionally on the happening of any event shall not be considered Voting Shares, nor shall any shares be deemed to cease to be Voting Shares solely by reason of a right to vote accruing to shares of another class or classes by reason of the happening of such an event, or solely because the right to vote may not be exercisable under the charter of the corporation.

Covenants

Limitation on Liens

        The Indenture provides that so long as any of our debt securities are outstanding and subject to the provisions of the Indenture, we will not, and will not permit any of our Restricted Subsidiaries to, create, incur, assume or otherwise have outstanding any Lien securing any indebtedness for borrowed money or interest thereon (or any liability of ours or such Restricted Subsidiaries under any guarantee or endorsement or other instrument under which we or such Restricted Subsidiaries are contingently liable, either directly or indirectly, for borrowed money or interest thereon), other than Permitted Liens, without also simultaneously or prior thereto securing, or causing such Restricted Subsidiaries to secure, indebtedness under the Indenture so that our debt securities are secured equally and ratably with or prior to such other indebtedness or liability, except that we and our Restricted Subsidiaries may incur a Lien to secure indebtedness for borrowed money without securing our debt securities if, after giving effect thereto, the principal amount of indebtedness for borrowed money secured by Liens created, incurred or assumed after the date of the Indenture and otherwise prohibited by the Indenture does not exceed 12% of our Consolidated Net Tangible Assets.

        Notwithstanding the foregoing, transactions such as the sale (including any forward sale) or other transfer of (i) oil, gas, minerals or other resources of a primary nature, whether in place or when produced, for a period of time until, or in an amount such that, the purchaser will realize therefrom a specified amount of money or a specified rate of return (however determined), or a specified amount of such oil, gas, minerals, or other resources of a primary nature, or (ii) any other interest in property of the character commonly referred to as a "production payment", will not constitute a Lien and will not result in us or a Restricted Subsidiary of ours being required to secure the debt securities.

Consolidation, Amalgamation, Merger and Sale of Assets

        We shall not consolidate or amalgamate with or merge into or enter into any statutory arrangement with any other corporation, partnership or trust, or convey, transfer or lease all or substantially all our properties and assets to any person, unless:

•

the entity formed by or continuing from such consolidation or amalgamation or into which we are merged or with which we enter into such statutory arrangement or the person which acquires or leases all or substantially all of our properties and assets is a corporation, partnership or trust organized and validly existing under the laws of the United States, any state thereof or the District of Columbia or the laws of Canada or any province or territory thereof, or, if such consolidation, amalgamation, merger, statutory arrangement or other transaction would not impair the rights of the holders of our debt securities, in any other country, provided that if such successor entity is organized under the laws of a jurisdiction other than the United States, any state thereof or the District of Columbia, or the laws of Canada or

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any province or territory thereof, the successor entity assumes our obligations under the debt securities and the Indenture to pay Additional Amounts, with the name of such successor jurisdiction being included in addition to Canada in each place that Canada appears in "— Payment of Additional Amounts" and "— Tax Redemption" below;

•

the successor entity expressly assumes or assumes by operation of law all of our obligations under our debt securities and under the Indenture;

•

immediately after giving effect to such transaction, no event of default, and no event which, after notice or lapse of time or both, would become an event of default, shall have happened and be continuing; and

•

certain other conditions are met.

        In addition, we may, notwithstanding anything in the Indenture, consolidate or amalgamate with or merge into or enter into a statutory arrangement with any direct or indirect wholly-owned Subsidiary and may convey, transfer or lease all or substantially all of our properties and assets to any direct or indirect wholly-owned Subsidiary without complying with the above provisions in a transaction or series of transactions in which we retain all of our obligations under and in respect of all outstanding debt securities under the Indenture (a "Permitted Reorganization") provided that on or prior to the date of the Permitted Reorganization, we deliver to the Trustee an officer's certificate confirming that, as of the date of the Permitted Reorganization:

•

substantially all of our unsubordinated and unsecured indebtedness for borrowed money which ranked pari passu with the then outstanding debt securities under the Indenture immediately prior to the proposed Permitted Reorganization will rank no better than pari passu with the then outstanding debt securities under the Indenture after the Permitted Reorganization; for certainty, there is no requirement for any such other indebtedness to obtain or maintain similar ranking to the then outstanding debt securities under the Indenture and such other indebtedness may be structurally subordinated or otherwise subordinated to the then outstanding debt securities under the Indenture; or

•

at least two of our then current credit rating agencies (or if only one credit rating agency maintains ratings in respect of the debt securities at such time, that one credit rating agency) have affirmed that the rating assigned by them to the debt securities shall not be downgraded as a result of the Permitted Reorganization.

        If, as a result of any such transaction, any of our or our Restricted Subsidiaries' Restricted Properties become subject to a Lien, then, unless such Lien could be created pursuant to the Indenture provisions described under the "Limitation on Liens" covenant above without equally and ratably securing our debt securities, we, simultaneously with or prior to such transaction, will secure, or cause the applicable Restricted Subsidiary to secure, our debt securities to be secured equally and ratably with or prior to the indebtedness secured by such Lien.

Payment of Additional Amounts

        Unless otherwise specified in the applicable prospectus supplement, all payments made by or on behalf of us under or with respect to any series of our debt securities will be

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made free and clear of and without withholding or deduction for or on account of any present or future tax, duty, levy, impost, assessment or other governmental charge (including penalties, interest and other liabilities related thereto) imposed or levied by or on behalf of the Government of Canada or any province or territory thereof or by any authority or agency therein or thereof having power to tax (hereinafter "Canadian Taxes"), unless we are required to withhold or deduct Canadian Taxes by law or by the interpretation or administration thereof. If we are so required to withhold or deduct any amount for or on account of Canadian Taxes from any payment made under or with respect to the debt securities, we will pay to each holder of such debt securities as additional interest such additional amounts ("Additional Amounts") as may be necessary so that the net amount received by each such holder (including the Additional Amounts) after such withholding or deduction (and after deducting any Canadian Taxes on such Additional Amounts) will not be less than the amount such holder would have received if such Canadian Taxes had not been withheld or deducted. However, no Additional Amounts will be payable with respect to a payment made to a debt securities holder (such holder, an "Excluded Holder") in respect of the beneficial owner thereof:

•

with which we do not deal at arm's length (for the purposes of the Income Tax Act (Canada)) at the time the amount is paid or payable;

•

which is subject to such Canadian Taxes by reason of the debt securities holder or beneficial owner being a resident, domicile or national of, or engaged in business or maintaining a permanent establishment or other physical presence in or otherwise having some connection with Canada or any province or territory thereof otherwise than by the mere holding of the debt securities or the receipt of payments thereunder; or

•

which is subject to such Canadian Taxes by reason of the debt securities holder's or beneficial owner's failure to comply with any certification, identification, information, documentation or other reporting requirements if compliance is required by law, regulation, administrative practice or an applicable treaty as a precondition to exemption from, or a reduction in the rate of deduction or withholding of, such Canadian Taxes.

        In addition, Additional Amounts will not be payable if the beneficial owner of, or person ultimately entitled to obtain an interest in, such debt securities is not the sole beneficial owner of such payments, or is a fiduciary or partnership, to the extent that any beneficial owner, beneficiary or settlor with respect to such fiduciary or any partner or member of such partnership would not have been entitled to such Additional Amounts with respect to such payments had such beneficial owner, beneficiary, settlor, partner or member received directly its beneficial or distributive shares of such payments. In addition, Additional Amounts will not be payable with respect to any Canadian Taxes which are payable otherwise than by withholding from payments of, or in respect of, principal of, or interest on, the debt securities.

        We will also:

•

make such withholding or deduction; and

•

remit the full amount deducted or withheld to the relevant authority in accordance with applicable law.

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        We will furnish to the holders of the debt securities, within 60 days after the date the payment of any Canadian Taxes is due pursuant to applicable law, certified copies of tax receipts or other documents evidencing such payment by us.

        We will indemnify and hold harmless each holder of debt securities (other than an Excluded Holder) and upon written request reimburse each such holder for the amount (excluding any Additional Amounts that have previously been paid by us with respect thereto) of:

•

the payment of any Canadian Tax, together with any interest, penalties and reasonable expenses in connection therewith; and

•

any Canadian Taxes imposed with respect to any reimbursement under the preceding clause, but excluding any such Canadian Taxes on such holder's net income.

        Notwithstanding the foregoing, provided that we are (or any successor is) an entity organized under the laws of the United States of America, any state thereof, or the District of Columbia, or the laws of Canada or any province or territory thereof, no Additional Amounts or indemnity amounts will be payable in excess of Additional Amounts or the indemnity amounts which would be required if the holder of debt securities was a resident of the United States and a "qualifying person" for purposes of the Canada-U.S. Income Tax Convention (1980), as amended.

        Wherever in the Indenture there is mentioned, in any context, the payment of principal (and premium, if any), interest, if any, or any other amount payable under or with respect to a debt security, such mention shall be deemed to include mention of the payment of Additional Amounts to the extent that, in such context, Additional Amounts are, were or would be payable in respect thereof.

Tax Redemption

        Unless otherwise specified in the applicable prospectus supplement, a series of our debt securities will be subject to redemption at any time, in whole and not in part, at a redemption price equal to the principal amount thereof together with accrued and unpaid interest to the date fixed for redemption, upon the giving of a notice as described below, if we or our successor determines that:

•

as a result of any change in or amendment to the laws (or any regulations or rulings promulgated thereunder) of Canada or of any political subdivision or taxing authority thereof or therein affecting taxation, or any change in official position regarding the application or interpretation of such laws, regulations or rulings (including a holding by a court of competent jurisdiction), which change or amendment is announced or becomes effective on or after the date specified in the applicable prospectus supplement or, if applicable, the date a person organized in a jurisdiction other than Canada or the United States becomes our successor pursuant to the consolidation covenant of the Indenture described above under "— Covenants — Consolidation, Amalgamation, Merger and Sale of Assets," we or our successor reasonably determines that we or our successor have or will become obligated to pay, on the next succeeding date on which interest is due, Additional Amounts with respect to any debt security of such series as described under "— Payment of Additional Amounts"; or

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•

on or after the date specified in the applicable prospectus supplement or, if applicable, the date a person organized in a jurisdiction other than Canada or the United States becomes our successor pursuant to the consolidation covenant of the Indenture, any action has been taken by any taxing authority of, or any decision has been rendered by a court of competent jurisdiction in Canada, or any political subdivision or taxing authority thereof or therein, including any of those actions specified in the paragraph immediately above, whether or not such action was taken or decision was rendered with respect to us, or our successor, or any change, amendment, application or interpretation shall be officially proposed, which, in any such case, in the written opinion to us of legal counsel of recognized standing, will likely result in us or our successor becoming obligated to pay, on the next succeeding date on which interest is due, Additional Amounts with respect to any debt security of such series;

and, in any such case, we, or our successor, in our business judgment, determine that such obligation cannot be avoided by the use of reasonable measures available to us or our successor.

        In the event that we elect to redeem a series of our debt securities pursuant to the provisions set forth in the preceding paragraph, we shall deliver to the Trustee a certificate, signed by an authorized officer, stating that we are entitled to redeem such series of our debt securities pursuant to their terms.

        Notice of intention to redeem such series of our debt securities will be given not more than 60 nor less than 30 days prior to the date fixed for redemption and will specify the date fixed for redemption.

Provision of Financial Information

        We will file with the Trustee, within 30 days after we file them with or furnish them to the SEC, copies, which may be in electronic format, of our annual and quarterly reports and of the information, documents and other reports (or copies of such portions of any of the foregoing as the SEC may by rules and regulations prescribe) which we are required to file with or furnish to the SEC pursuant to Section 13 or 15(d) of the Exchange Act.

        Notwithstanding that we may not be required to remain subject to the reporting requirements of Section 13 or 15(d) of the Exchange Act or otherwise report on an annual and quarterly basis on forms provided for such annual and quarterly reporting pursuant to rules and regulations promulgated by the SEC, we will continue to provide the Trustee:

•

within 140 days after the end of each fiscal year, the information required to be contained in annual reports on Form 20-F, Form 40-F or Form 10-K as applicable (or any successor form); and

•

within 65 days after the end of each of the first three fiscal quarters of each fiscal year, the information required to be contained in reports on Form 6-K (or any successor form) which, regardless of applicable requirements shall, at a minimum, contain such information required to be provided in quarterly reports under the laws of Canada or any province thereof to security holders of a corporation with securities listed on the Toronto Stock Exchange, whether or not we have any of our securities listed on such exchange. Such information will be prepared in accordance with Canadian disclosure requirements and GAAP, to the extent permitted by the rules and regulations

23

of the SEC, provided, however, that we shall not be obligated to file such report with the SEC if the SEC does not permit such filings.

Events of Default

        The following are summaries of events of default under the Indenture with respect to any series of our debt securities:

•

default in the payment of any interest on any debt security of that series when such interest becomes due and payable, and continuance of such default for a period of 30 days;

•

default in the payment of the principal of (or premium, if any, on), any debt security of that series when it becomes due and payable;

•

default in the performance, or breach, of any of our covenants or warranties in the Indenture in respect of our debt securities of that series (other than a covenant or warranty a default in the performance of which or the breach of which is specifically dealt with elsewhere in the Indenture), and continuance of such default or breach for a period of 60 days after receipt by us of written notice to us, specifying such default or breach, by the Trustee or by the holders of at least 25% in principal amount of all outstanding debt securities of any series affected thereby;

•

if an event of default (as defined in any indenture or instrument under which we or one of our Restricted Subsidiaries has at the time of the Indenture or shall thereafter have outstanding any indebtedness for borrowed money) shall happen and be continuing, or we or any of our Restricted Subsidiaries shall have failed to pay principal amounts with respect to such indebtedness at maturity and such event of default or failure to pay shall result in such indebtedness being declared due and payable or otherwise being accelerated, in either event so that an amount in excess of the greater of US$150,000,000 (or its equivalent in any other currency) and 3.5% of our Shareholders' Equity shall be or become due and payable upon such declaration or otherwise accelerated prior to the date on which the same would otherwise have become due and payable (the "accelerated indebtedness"), and such acceleration shall not be rescinded or annulled, or such event of default or failure to pay under such indenture or instrument shall not be remedied or cured, whether by payment or otherwise, or waived by the holders of such accelerated indebtedness, then (i) if the accelerated indebtedness shall be as a result of an event of default which is not related to the failure to pay principal or interest on the terms, at the times, and on the conditions set out in any such indenture or instrument, it shall not be considered an event of default for purposes of the Indenture until 30 days after such indebtedness has been accelerated, or (ii) if the accelerated indebtedness shall occur as a result of such failure to pay principal or interest or as a result of an event of default which is related to the failure to pay principal or interest on the terms, at the times, and on the conditions set out in any such indenture or instrument, then (A) if such accelerated indebtedness is, by its terms, Non-Recourse Debt to us or our Restricted Subsidiaries, it shall not be considered an event of default for purposes of the Indenture; or (B) if such accelerated indebtedness is recourse to us or our Restricted Subsidiaries, any requirement in connection with such failure to pay or event of default for the giving of notice or the lapse of time or the happening of any further condition, event or

24

act under such other indenture or instrument in connection with such failure to pay principal or an event of default shall be applicable together with an additional seven days before being considered an event of default for purposes of the Indenture;

•

the entry of a decree or order by a court having jurisdiction in the premises adjudging us a bankrupt or insolvent, or approving as properly filed a petition seeking reorganization, arrangement, adjustment or composition of or in respect of us under the Bankruptcy and Insolvency Act (Canada), the Companies' Creditors Arrangement Act (Canada) or any other applicable insolvency law, or appointing a receiver, liquidator, assignee, trustee, sequestrator (or similar official) of us or of any substantial part of our property, or ordering the winding up or liquidation of our the affairs, and the continuance of any such decree or order unstayed and in effect for a period of 90 consecutive days;

•

the institution by us of proceedings to be adjudicated a bankrupt or insolvent, or the consent by us to the institution of bankruptcy or insolvency proceedings against us, or the filing by us of a petition or answer or consent seeking reorganization or relief under the Bankruptcy and Insolvency Act (Canada), the Companies' Creditors Arrangement Act (Canada) or any other applicable insolvency law, or the consent by us to the filing of any such petition or to the appointment of a receiver, liquidator, assignee, trustee, sequestrator (or other similar official) of us or of any substantial part of our property, or the making by us of an assignment for the benefit of creditors, or the admission by us in writing of our inability to pay our debts generally as they become due; or

•

any other events of default provided with respect to debt securities of that series.

        If an event of default under the Indenture occurs and is continuing with respect to any series of our debt securities, then and in every such case the Trustee or the holders of not less than 25% in aggregate principal amount of the outstanding debt securities of such affected series may, subject to any subordination provisions thereof, declare the entire principal amount (or, if the debt securities of that series are original issue discount debt securities or indexed securities, such portion of the principal amount as may be specified in the terms of that series) of all debt securities of such series and all accrued and unpaid interest thereon to be immediately due and payable. However, at any time after a declaration of acceleration with respect to any series of our debt securities has been made, but before a judgment or decree for payment of the money due has been obtained, the holders of a majority in principal amount of the outstanding debt securities of that series, by written notice to us and the Trustee under certain circumstances, may rescind and annul such acceleration.

        Reference is made to the applicable prospectus supplement or supplements relating to each series of our debt securities which are original issue discount debt securities for the particular provisions relating to acceleration of the maturity of a portion of the principal amount of such original issue discount securities upon the occurrence of any event of default and the continuation thereof.

        Subject to certain limitations set forth in the Indenture, the holders of a majority in principal amount of the outstanding debt securities of all series affected by an event of default 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

25

conferred on the Trustee, with respect to the debt securities of all series affected by such event of default.

        No holder of a debt security of any series will have any right to institute any proceeding with respect to the Indenture, debt securities of any series or for the appointment of a receiver or a Trustee, or for any other remedy thereunder, unless:

•

such holder has previously given to the Trustee written notice of a continuing event of default with respect to the debt securities of such series affected by such event of default;

•

the holders of not less than 25% in aggregate principal amount of the outstanding debt securities of such series affected by such event of default have made written request, and such holder or holders have offered reasonable indemnity, to the Trustee to institute such proceeding as Trustee; and

•

the Trustee has failed to institute such proceeding, and has not received from the holders of a majority in aggregate principal amount of the outstanding debt securities of such series affected by such event of default a direction inconsistent with such request, within 60 days after such notice, request and offer.

        However, such above-mentioned limitations do not apply to a suit instituted by the holder of a debt security for the enforcement of payment of the principal of or any premium or interest on such debt security on or after the applicable due date specified in such debt security.

        We will annually furnish to the Trustee a statement by certain of our officers as to whether or not we, to the best of their knowledge, are in compliance with all conditions and covenants of the Indenture and, if not, specifying all such known defaults.

Defeasance and Covenant Defeasance

        Unless otherwise specified in the applicable prospectus supplement, the Indenture provides that, at our option, we will be discharged from any and all obligations in respect of the outstanding debt securities of any series upon irrevocable deposit with the Trustee, in trust, of money and/or government securities which will provide money in an amount sufficient in the opinion of a nationally recognized firm of independent chartered accountants (as evidenced by an officer's certificate delivered to the Trustee) to pay the principal of (and premium, if any, and each instalment of interest, if any, on) the outstanding debt securities of such series (hereinafter referred to as a "defeasance") (except with respect to the authentication, transfer, exchange or replacement of our debt securities or the maintenance of a place of payment and certain other obligations set forth in the Indenture). Such trust may only be established if among other things:

•

we have delivered to the Trustee an opinion of counsel in the United States stating that (i) we have received from, or there has been published by, the Internal Revenue Service a ruling, or (ii) since the date of execution of the Indenture, there has been a change in the applicable U.S. federal income tax law, in either case to the effect that the holders of the outstanding debt securities of such series will not recognize income, gain or loss for U.S. federal income tax purposes as a result of such defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner

26

and at the same times as would have been the case if such defeasance had not occurred;

•

we have delivered to the Trustee an opinion of counsel in Canada or a ruling from the Canada Revenue Agency (or successor agency) to the effect that the holders of the outstanding debt securities of such series should not recognize income, gain or loss for Canadian federal or provincial income tax or other purposes as a result of such defeasance and should be subject to Canadian federal or provincial income tax on the same amounts, in the same manner and at the same times as would have been the case had such defeasance not occurred (and for the purposes of such opinion, such Canadian counsel shall assume that holders of the outstanding debt securities of such series include holders who are not resident in Canada);

•

no event of default or event that, with the passing of time or the giving of notice, or both, shall constitute an event of default shall have occurred and be continuing on the date of such deposit; and

•

we are not an "insolvent person" within the meaning of the Bankruptcy and Insolvency Act (Canada) on the date of such deposit or at any time during the period ending on the 91^st day following such deposit.

        We may exercise our defeasance option notwithstanding our prior exercise of our covenant defeasance option described in the following paragraph if we meet the conditions described in the preceding sentence at the time we exercise the defeasance option.

        The Indenture provides that, at our option, unless and until we have exercised our defeasance option described in the preceding paragraph, we may omit to comply with the "Limitation on Liens" covenant, certain aspects of the "Consolidation, Amalgamation, Merger and Sale of Assets" covenant and certain other covenants and such omission shall not be deemed to be an event of default under the Indenture and our outstanding debt securities upon irrevocable deposit with the Trustee, in trust, of money and/or government securities which will provide money in an amount sufficient in the opinion of a nationally recognized firm of independent chartered accountants (as evidenced by an officer's certificate delivered to the Trustee) to pay the principal of (and premium, if any, and each installment of interest, if any, on) the outstanding debt securities (hereinafter referred to as "covenant defeasance"). If we exercise our covenant defeasance option, the obligations under the Indenture other than with respect to such covenants and the events of default other than with respect to such covenants shall remain in full force and effect. Such trust may only be established if, among other things:

•

we have delivered to the Trustee an opinion of counsel in the United States to the effect that the holders of our outstanding debt securities will not recognize income, gain or loss for U.S. federal income tax purposes as a result of such covenant defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such covenant defeasance had not occurred;

•

we have delivered to the Trustee an opinion of counsel in Canada or a ruling from the Canada Revenue Agency (or successor agency) to the effect that the holders of our outstanding debt securities should not recognize income, gain or loss for Canadian federal or provincial income or other tax purposes as a result of such covenant defeasance and should be subject to Canadian federal or provincial income and other tax on the same amounts, in the same manner

27

and at the same times as would have been the case had such covenant defeasance not occurred (and for the purposes of such opinion, such Canadian counsel shall assume that holders of our outstanding debt securities include holders who are not resident in Canada);

•

no event of default or event that, with the passing of time or the giving of notice, or both, shall constitute an event of default shall have occurred and be continuing on the date of such deposit; and

•

we are not an "insolvent person" within the meaning of the Bankruptcy and Insolvency Act (Canada) on the date of such deposit or at any time during the period ending on the 91^st day following such deposit.

Modification and Waiver

        Modifications and amendments of the Indenture may be made by us and the Trustee with the consent of the holders of a majority in principal amount of the outstanding debt securities of each series issued under the Indenture affected by such modification or amendment; provided, however, that no such modification or amendment may, among other things, without the consent of the holder of each outstanding debt security of such affected series:

•

change the stated maturity of the principal of (or premium, if any), or any installment of interest, if any, on any debt security;

•

reduce the principal amount of (or premium, if any, or interest, if any, on) any debt security;

•

reduce the amount of principal of a debt security payable upon acceleration of the maturity thereof;

•

change the place of payment;

•

change the currency of payment of principal of (or premium, if any, or interest, if any, on) any debt security;

•

impair the right to institute suit for the enforcement of any payment on or with respect to any debt security;

•

reduce the percentage of principal amount of outstanding debt securities of such series, the consent of the holders of which is required for modification or amendment of the applicable Indenture or for waiver of compliance with certain provisions of the Indenture or for waiver of certain defaults; or

•

modify any provisions of the Indenture relating to the modification and amendment of the Indenture or the waiver of past defaults or covenants except as otherwise specified in the Indenture.

        The holders of a majority in principal amount of our outstanding debt securities of any series may on behalf of the holders of all debt securities of that series waive, insofar as that series is concerned, compliance by us with certain restrictive provisions of the Indenture. The holders of a majority in principal amount of outstanding debt securities of any series may waive any past or existing default under the Indenture with respect to that series, except a default in the payment of the principal of (or premium, if any) and interest,

28

if any, on any debt security of that series or in respect of a provision which under the Indenture cannot be modified or amended without the consent of the holder of each outstanding debt security of that series.

        The Indenture or the debt securities may be amended or supplemented, without the consent of any holder of such debt securities, in order to, among other things, cure any ambiguity or inconsistency or to make any change, in any case, that does not have a materially adverse effect on the rights of any holder of such debt securities.

Consent to Jurisdiction and Service

        Under the Indenture, we irrevocably appoint CT Corporation System, 111-8^th Avenue, New York, New York, 10011 as our authorized agent for service of process in any suit or proceeding arising out of or relating to our debt securities or the Indenture and for actions brought under federal or state securities laws in any federal or state court located in New York, New York and irrevocably submit to the non-exclusive jurisdiction of any such court.

Governing Law

        Our debt securities and the Indenture will be governed by and construed in accordance with the laws of the State of New York.

RISK FACTORS

In addition to the risk factors set forth below, additional risk factors relating to our business are discussed in our Annual Information Form, our annual Management's Discussion and Analysis and certain other documents incorporated by reference or deemed to be incorporated by reference herein, which risk factors are incorporated by reference herein. Prospective purchasers of the debt securities should consider carefully the risk factors set forth below, as well as the other information contained in and incorporated by reference in this prospectus and in the applicable prospectus supplement before purchasing the debt securities offered hereby. If any event arising from these risks occurs, our business, prospects, financial condition, results of operations or cash flows, or your investment in the debt securities could be materially adversely affected.

There is an absence of a public market for the debt securities and there can be no assurance as to the liquidity of the trading market for the debt securities or that a trading market for the debt securities will develop.

        There is no public market for the debt securities and we do not intend to apply for listing of the debt securities on any securities exchange. If the debt securities are traded after their initial issue, they may trade at a discount from their initial offering prices depending on prevailing interest rates, the market for similar securities and other factors, including general economic conditions and our financial condition. There can be no assurance as to the liquidity of any trading market for the debt securities or that a trading market for the debt securities will develop.

In certain circumstances the debt securities may be subordinated to the security interests of our lenders and the indebtedness of our subsidiaries and partnerships.

        The debt securities are not subordinated to any other indebtedness and they are not secured. Although our various debt instruments restrict secured indebtedness, such

29

indebtedness may be incurred, subject to certain conditions. In addition, our subsidiaries and partnerships may incur indebtedness, subject to certain limitations. The debt securities will be effectively subordinated to creditors of our subsidiaries and partnerships, in that our right to participate as a stockholder or partner in the distribution of the assets of any subsidiary or partnership, as the case may be, upon any such distribution would be subject to the prior claims of the creditors of such subsidiary or partnership, as the case may be. We conduct a substantial portion of our business through corporate and partnership subsidiaries.

        The Indenture permits us, at any time and from time to time, to complete reorganizations with any of our wholly-owned direct or indirect subsidiaries provided that certain conditions are met. In the event of any such reorganization, the debt securities may continue to be our obligations in circumstances where our assets are comprised of (and potentially limited to) our ownership interest in the subsidiaries through which our operations are thereafter conducted. Such subsidiaries, which following completion of a reorganization may hold all of the assets formerly held by us, are not restricted under the Indenture with respect to subsequent asset dispositions or incurring indebtedness. See "Description of Debt Securities — Covenants — Consolidation, Amalgamation, Merger and Sale of Assets".

In the event that the debt securities are redeemable, purchasers of the debt securities may be adversely impacted.

        If the debt securities are redeemable at our option, as set forth in the applicable prospectus supplement, we may choose to redeem the debt securities from time to time, in accordance with our rights under the Indenture, including when prevailing interest rates are lower than the rates borne by the debt securities. If prevailing rates are lower at the time of redemption, a purchaser may not be able to reinvest the redemption proceeds in a comparable security at an effective interest rate as high as the interest rate on the debt securities being redeemed. Redemption rights may also adversely impact a purchaser's ability to sell debt securities as the optional redemption date or period approaches.

Credit ratings accorded to the debt securities may not remain in effect or may change in the future and may not reflect all risks associated with an investment in the debt securities.

        Our perceived creditworthiness and changes in credit ratings of the Notes may affect the market price or value and the liquidity of the Notes. There is no assurance that the ratings accorded to the debt securities will remain in effect for any given period of time or that the ratings will not be revised or withdrawn entirely in the future by the relevant rating agency. Real or anticipated changes in credit ratings on the debt securities may affect the market value of the debt securities. In addition, real or anticipated changes in credit ratings can affect the cost of or terms on which we can issue debentures or incur other debt.

        Credit ratings assigned to us and to the debt securities by independent rating agencies may not reflect all risks associated with an investment in the debt securities. Any credit ratings applied to the debt securities are an independent assessment of our ability to pay obligations. The credit ratings, however, may not reflect the potential impact of risks related to structure, market or other factors discussed in this short form prospectus or documents incorporated by reference in this short form prospectus on the value of the debt securities.

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Prevailing interest rates for comparable securities will affect the market price or value of the debt securities.

        Prevailing interest rates will affect the market price or value of the debt securities. Assuming all other factors remain unchanged, the market price or value of the debt securities may decline as prevailing interest rates for comparable debt instruments rise.

In the event that the debt securities are issued with a floating rate of interest, purchasers of the debt securities may be adversely impacted.

        An investment in debt securities which are issued with a floating rate of interest entails significant risks not associated with investments in fixed rate debt securities. The resetting of the applicable rate on a floating rate debt security may result in lower interest compared to a fixed rate debt security issued at the same time. The applicable rate on a floating rate debt security will fluctuate in accordance with fluctuations in the instrument or obligation on which the applicable rate is based, which in turn may fluctuate and be affected by a number of interrelated factors, including economic, financial and political events over which we have no control.

CERTAIN INCOME TAX CONSIDERATIONS

        The applicable prospectus supplement will describe certain Canadian federal income tax consequences to an investor of acquiring any debt securities offered thereunder, including, for investors who are non-residents of Canada, whether the payments of principal and interest, if any, will be subject to Canadian withholding tax.

        The applicable prospectus supplement will also describe certain U.S. federal income tax consequences of the acquisition, ownership and disposition of any debt securities offered thereunder by an initial investor who is a U.S. person (within the meaning of the U.S. Internal Revenue Code), including, to the extent applicable, any such consequences relating to debt securities payable in a currency other than the U.S. dollar, issued at an original issue discount for U.S. federal income tax purposes or containing early redemption provisions or other special items.

PLAN OF DISTRIBUTION

        We may offer and sell debt securities to or through underwriters or dealers and also may sell debt securities directly to purchasers or through agents. These debt securities may be offered and sold in the United States and elsewhere where permitted by law.

        The distribution of debt securities of any series may be effected from time to time in one or more transactions:

•

at a fixed price or prices, which may be changed;

•

at market prices prevailing at the time of sale; or

•

at prices related to such prevailing market prices to be negotiated with purchasers.

        In connection with the sale of debt securities, underwriters may receive compensation from us or from purchasers of debt securities for whom they may act as agents in the form of concessions or commissions. Underwriters, dealers and agents that participate in the distribution of debt securities may be deemed to be underwriters and any

31

commissions received by them from us and any profit on the resale of debt securities by them may be deemed to be underwriting commissions under the United States Securities Act of 1933, as amended (the "Securities Act").

        The prospectus supplement relating to each series of debt securities will also set forth the terms of the offering of the debt securities, including to the extent applicable, the initial offering price, our proceeds from the offering, the underwriting concessions or commissions, and any other discounts or concessions to be allowed or reallowed to dealers. Underwriters with respect to each series sold to or through underwriters will be named in the prospectus supplement relating to such series.

        Under agreements which may be entered into by us, underwriters, dealers and agents who participate in the distribution of debt securities may be entitled to indemnification by us against certain liabilities, including liabilities under the Securities Act. The underwriters, dealers and agents with whom we enter into agreements may be customers of, engage in transactions with or perform services for us in the ordinary course of business.

        Each series of debt securities will be a new issue of securities with no established trading market. Unless otherwise specified in a prospectus supplement relating to a series of debt securities, the debt securities will not be listed on any securities exchange or on any automated dealer quotation system. Certain broker-dealers may make a market in the debt securities, but will not be obligated to do so and may discontinue any market making at any time without notice. We cannot assure you that any broker-dealer will make a market in the debt securities of any series or as to the liquidity of the trading market, if any, for the debt securities of any series.

INTEREST COVERAGE

        The following sets forth our interest coverage ratios calculated for the twelve month periods ended December 31, 2013, based on audited financial information and March 31, 2014, based on unaudited financial information. The interest coverage ratios do not give effect to the debt securities offered by this short form prospectus since the aggregate principal amount of debt securities that will be issued hereunder and the terms of issue are not presently known. The interest coverage ratios set forth below do not purport to be indicative of the interest coverage ratios for any future periods.

        Our borrowing costs on all interest bearing financial liabilities amounted to $369 million and $370 million for the twelve months ended December 31, 2013 and March 31, 2014, respectively. Our net earnings plus income tax, borrowing costs on all interest bearing financial liabilities and premium on redemption of long-term debt for the twelve months ended December 31, 2013 and March 31, 2014 was $1,496 million and $1,561 million, respectively.

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	December 31, 2013	March 31, 2014
Interest coverage:
Net earnings available for all interest bearing financial liabilities(1)	4.1 times	4.2 times
Net earnings available for short-term borrowings and long-term debt before unrealized (gains) and losses on risk management activities(2)	6.7 times	5.9 times

Notes:

(1)

Calculated as net earnings plus income tax, borrowing costs on all financial liabilities and premium on redemption of long-term debt; divided by borrowing costs for all interest bearing financial liabilities.

(2)

Calculated as net earnings plus income tax, interest on short-term borrowings and long-term debt, premium on redemption of long-term debt and before unrealized (gains) and losses on risk management activities; divided by interest expense on short-term borrowings and long-term debt.

        The Company believes the interest coverage ratio based on net earnings available for short-term borrowings and long-term debt and before unrealized (gains) and losses on risk management activities is a relevant measure for investors as the realization of unrealized (gains) and losses are yet to be determined and will be realized in future periods. Additionally, the Company's balance sheet previously included a partnership contribution receivable (collected on December 17, 2013) and a partnership contribution payable (repaid on March 28, 2014), that arose due to a structuring arrangement. The interest income and interest expense from this structuring arrangement substantially offset each other in the past, will not be recorded in any future periods and as such the interest expense has been excluded from this interest coverage ratio.

LEGAL MATTERS

        Unless otherwise specified in the prospectus supplement relating to a series of debt securities, certain legal matters relating to Canadian law will be passed upon for us by Norton Rose Fulbright Canada LLP, Calgary, Alberta, Canada. Certain legal matters in connection with the offering relating to United States law will be passed upon for us by Paul, Weiss, Rifkind, Wharton & Garrison LLP, New York, New York.

        The partners and associates of Norton Rose Fulbright Canada LLP as a group beneficially own, directly or indirectly, less than 1% of any class of our securities.

EXPERTS

        The audited annual consolidated financial statements and management's assessment of the effectiveness of internal control over financial reporting incorporated by reference in this prospectus have been so incorporated in reliance on the audit reports which are also incorporated by reference in this prospectus, of PricewaterhouseCoopers LLP, Chartered Accountants, as experts in auditing and accounting.

        Information relating to our reserves in the Annual Information Form dated February 12, 2014 was calculated based on evaluations of and reports on our crude oil and natural gas reserves conducted and prepared by GLJ Petroleum Consultants Ltd. and McDaniel & Associates Consultants Ltd. as independent qualified reserve evaluators. The principals of

33

each of GLJ Petroleum Consultants Ltd. and McDaniel & Associates Consultants Ltd., in each case, as a group own beneficially, directly or indirectly, less than 1% of any class of our securities.

AGENT FOR SERVICE OF PROCESS IN CANADA

        Messrs. Cunningham and Rampacek are directors of Cenovus who reside outside of Canada and each of these directors has appointed Cenovus for service of process at 2600, 500 Centre Street S.E., Calgary, Alberta T2G 1A6. Purchasers are advised that it may not be possible for investors to enforce judgments obtained in Canada against any person who resides outside of Canada, even if the party has appointed an agent for service of process.

ENFORCEABILITY OF CIVIL LIABILITIES

        We are a corporation incorporated under and governed by the Canada Business Corporations Act. Most of our directors and officers, and some or all of the experts named in this prospectus, are residents of Canada or otherwise reside outside of the United States, and a substantial portion of their assets, and a substantial portion of our assets, are located outside the United States. We have appointed an agent for service of process in the United States, but it may be difficult for holders of debt securities who reside in the United States to effect service within the Unites States upon those directors, officers and experts who are not residents of the United States. It may also be difficult for holders of debt securities who reside in the United States to realize in the United States upon judgments of courts of the United States predicated upon our civil liability and the civil liability of our directors and officers and experts under the United States federal securities laws. We have been advised by our Canadian counsel, Norton Rose Fulbright Canada LLP, that a judgment of a United States court predicated solely upon civil liability under U.S. federal securities laws would probably be enforceable in Canada if the United States court in which the judgment was obtained has a basis for jurisdiction in the matter that would be recognized by a Canadian court for the same purposes. We have also been advised by Norton Rose Fulbright Canada LLP, however, that there is a substantial doubt whether an action could be brought in Canada in the first instance on the basis of liability predicated solely upon U.S. federal securities laws.

        We filed with the SEC, concurrently with our registration statement on Form F-10 of which this prospectus forms a part, an appointment of agent for service of process on Form F-X. Under the Form F-X, we appointed CT Corporation System as our agent for service of process in the United States in connection with any investigation or administrative proceeding conducted by the SEC and any civil suit or action brought against or involving us in a United States court arising out of or related to or concerning the offering of debt securities under this prospectus.

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DOCUMENTS FILED AS PART OF THE REGISTRATION STATEMENT

        The following documents have been or will be filed with the SEC as part of the registration statement of which this prospectus is a part insofar as required by the SEC's Form F-10:

•

the documents listed in the third paragraph under "Where You Can Find More Information" in this prospectus;

•

the consent of our accountants, PricewaterhouseCoopers LLP;

•

the consent of our Canadian counsel, Norton Rose Fulbright Canada LLP;

•

the consents of our independent qualified reserves evaluators, GLJ Petroleum Consultants Ltd. and McDaniel & Associates Consultants Ltd.;

•

powers of attorney from our directors and officers;

•

the trust indenture, dated as of August 17, 2012; and

•

the statement of eligibility of the trustee on Form T-1.

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PART II

INFORMATION NOT REQUIRED TO BE DELIVERED
TO OFFEREES OR PURCHASERS

Indemnification of Directors and Officers

        Under Section 124 of the Canada Business Corporations Act (the "CBCA"), Cenovus Energy Inc. ("Cenovus") may indemnify a present or former director or officer of Cenovus or another individual who acts or acted at Cenovus' request as a director or officer, or an individual acting in a similar capacity, of another entity, against all costs, charges and expenses, including an amount paid to settle an action or satisfy a judgment, reasonably incurred by the individual in respect of any civil, criminal, administrative, investigative or other proceeding in which the individual is involved because of that association with Cenovus or other entity. Cenovus may not indemnify an individual unless the individual acted honestly and in good faith with a view to the best interests of Cenovus, or, as the case may be, to the best interests of the other entity for which the individual acted as a director or officer or in a similar capacity at Cenovus' request and in the case of a criminal or administrative action or proceeding that is enforced by a monetary penalty, the individual had reasonable grounds for believing that the conduct was lawful. The indemnification may be made in connection with a derivative action only with court approval. The aforementioned individuals are entitled to indemnification from Cenovus as a matter of right if they were not judged by the court or other competent authority to have committed any fault or omitted to do anything that the individual ought to have done. Cenovus may advance moneys to a director, officer or other individual for the costs, charges and expenses of an aforementioned proceeding; however, the individual shall repay the moneys if the individual does not fulfill the conditions set out above.

        The by-laws of Cenovus provide that, subject to the limitations contained in the CBCA, but without limit to the right of Cenovus to indemnify any person under the CBCA or otherwise, Cenovus shall indemnify a director or officer of Cenovus, a former director or officer of Cenovus or another individual who acts or acted at Cenovus' request as a director or officer, or an individual acting in a similar capacity, of another entity, against all costs, charges and expenses, including an amount paid to settle an action or satisfy a judgment, reasonably incurred by the individual in respect of any civil, criminal, administrative, investigative or other proceeding in which the individual is involved because of that association with Cenovus or other entity, if the individual acted honestly and in good faith with a view to the best interests of Cenovus, or, as the case may be, to the best interests of the other entity for which the individual acted as director or officer or in a similar capacity at Cenovus' request, and in the case of a criminal or administrative action or proceeding that is enforced by a monetary penalty, the individual had reasonable grounds for believing that the individual's conduct was lawful.

        The by-laws of Cenovus provide that Cenovus may, subject to the limitations contained in the CBCA, purchase, maintain, or participate in insurance for the benefit of a director or officer of Cenovus, a former director or officer of Cenovus, or another individual who acts or acted at Cenovus' request as a director or officer, or an individual acting in a similar capacity, of another entity, as the Board may from time to time determine.

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

EXHIBITS

Exhibit Number		Description
	4.1	Annual Information Form of Cenovus Energy Inc. for the year ended December 31, 2013 (incorporated by reference to the Form 40-F of Cenovus Energy Inc. filed with the Securities and Exchange Commission on February 19, 2014) (File No. 1-34513).
	4.2	Audited Consolidated Financial Statements of Cenovus Energy Inc. for the year ended December 31, 2013 (incorporated by reference to the Form 40-F of Cenovus Energy Inc. filed with the Securities and Exchange Commission on February 19, 2014) (File No. 1-34513).
	4.3	Management's Discussion and Analysis of Cenovus Energy Inc. for the year ended December 31, 2013 (incorporated by reference to the Form 40-F of Cenovus Energy Inc. filed with the Securities and Exchange Commission on February 19, 2014) (File No. 1-34513).
	4.4	Unaudited Interim Consolidated Financial Statements of Cenovus Energy Inc. for the period ended March 31, 2014 (incorporated by reference to the Form 6-K of Cenovus Energy Inc. filed with the Securities and Exchange Commission on April 30, 2014) (File No. 1-34513).
	4.5	Management's Discussion and Analysis of Cenovus Energy Inc. for the three months ended March 31, 2014 (incorporated by reference to the Form 6-K of Cenovus Energy Inc. filed with the Securities and Exchange Commission on April 30, 2014) (File No. 1-34513).
	4.6	Management Proxy Circular of Cenovus Energy Inc., dated March 7, 2014, relating to the annual meeting of shareholders of Cenovus Energy Inc. held on April 30, 2014 (incorporated by reference to Cenovus Energy Inc.'s Form 6-K filed with the Securities and Exchange Commission on March 27, 2014) (File No. 1-34513).
	4.7	Supplementary Information — Oil and Gas Activities (unaudited) for the fiscal year ended December 31, 2013 (incorporated by reference to the Form 40-F of Cenovus Energy Inc. filed with the Securities and Exchange Commission on February 19, 2014) (File No. 1-34513).
	5.1	Consent of PricewaterhouseCoopers LLP.
	5.2†	Consent of Norton Rose Fulbright Canada LLP.
	5.3†	Consent of GLJ Petroleum Consultants Ltd.
	5.4†	Consent of McDaniel & Associates Consultants Ltd.
	6.1	Powers of Attorney (included on the signature page to this Registration Statement).
	7.1	Indenture, dated as of August 17, 2012, between Cenovus Energy Inc. and The Bank of New York Mellon, as Trustee (incorporated by reference to the Form 6-K of Cenovus Energy Inc. filed with the Securities and Exchange Commission on June 12, 2014) (File No. 1-34513).
	7.2	Statement of Eligibility of The Bank of New York Mellon on Form T-1.

†

To be filed by amendment.

PART III

UNDERTAKING AND CONSENT TO SERVICE OF PROCESS

Item 1.    Undertaking

        The Registrant undertakes to make available, in person or by telephone, representatives to respond to inquiries made by the Commission staff, and to furnish promptly, when requested to do so by the Commission staff, information relating to the securities registered pursuant to Form F-10 or to transactions in said securities.

Item 2.    Consent to Service of Process

        Concurrent with the filing of this Registration Statement on Form F-10, the Registrant has filed with the Commission a written irrevocable consent and power of attorney on Form F-X.

        Any change to the name or address of the agent for service of process of the Registrant shall be communicated promptly to the Commission by an amendment to the Form F-X referencing the file number of this Registration Statement.

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form F-10 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 June 12, 2014.

CENOVUS ENERGY INC.
By:	/s/ Brian C. Ferguson
	Name:	Brian C. Ferguson
	Title:	President & Chief Executive Officer

POWERS OF ATTORNEY

        Each person whose signature appears below hereby constitutes and appoints Brian C. Ferguson, Kerry D. Dyte and Ivor M. Ruste, and each of them, any of whom may act without the joinder of the other, the true and lawful attorney-in-fact and agent of the undersigned, with full power of substitution and resubstitution, for and in the name, place and stead of the undersigned, in any and all capacities, to sign any and all amendments to this Registration Statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, and hereby grants to such attorney-in-fact and agent, 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 the undersigned might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

        This Power of Attorney may be executed in multiple counterparts, each of which shall be deemed an original, but which taken together shall constitute one instrument.

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

Signature	Title	Date
/s/ Brian C. Ferguson Brian C. Ferguson	President & Chief Executive Officer and Director (Principal Executive Officer)	June 12, 2014
/s/ Ivor M. Ruste Ivor M. Ruste	Executive Vice-President & Chief Financial Officer (Principal Financial and Accounting Officer)	June 12, 2014
/s/ Michael A. Grandin Michael A. Grandin	Chair of the Board of Directors	June 12, 2014
/s/ Ralph S. Cunningham Ralph S. Cunningham	Director	June 12, 2014
/s/ Patrick D. Daniel Patrick D. Daniel	Director	June 12, 2014
/s/ Ian W. Delaney Ian W. Delaney	Director	June 12, 2014
/s/ Valerie A.A. Nielsen Valerie A.A. Nielsen	Director	June 12, 2014
/s/ Charles M. Rampacek Charles M. Rampacek	Director	June 12, 2014
/s/ Colin Taylor Colin Taylor	Director	June 12, 2014
/s/ Wayne G. Thomson Wayne G. Thomson	Director	June 12, 2014

AUTHORIZED REPRESENTATIVE

        Pursuant to the requirements of Section 6(a) of the Securities Act of 1933, as amended, the Authorized Representative has duly caused this Registration Statement to be signed on its behalf by the undersigned, solely in its capacity as the duly authorized representative of Cenovus Energy Inc. in the United States, on June 12, 2014.

CENOVUS DOWNSTREAM SERVICES LLC
By:	/s/ Larry A. Hofstetter
	Name:	Larry A. Hofstetter
	Title:	President

EXHIBITS INDEX

Exhibit Number		Description
	4.1	Annual Information Form of Cenovus Energy Inc. for the year ended December 31, 2013 (incorporated by reference to the Form 40-F of Cenovus Energy Inc. filed with the Securities and Exchange Commission on February 19, 2014) (File No. 1-34513).
	4.2	Audited Consolidated Financial Statements of Cenovus Energy Inc. for the year ended December 31, 2013 (incorporated by reference to the Form 40-F of Cenovus Energy Inc. filed with the Securities and Exchange Commission on February 19, 2014) (File No. 1-34513).
	4.3	Management's Discussion and Analysis of Cenovus Energy Inc. for the year ended December 31, 2013 (incorporated by reference to the Form 40-F of Cenovus Energy Inc. filed with the Securities and Exchange Commission on February 19, 2014) (File No. 1-34513).
	4.4	Unaudited Interim Consolidated Financial Statements of Cenovus Energy Inc. for the period ended March 31, 2014 (incorporated by reference to the Form 6-K of Cenovus Energy Inc. filed with the Securities and Exchange Commission on April 30, 2014) (File No. 1-34513).
	4.5	Management's Discussion and Analysis of Cenovus Energy Inc. for the three months ended March 31, 2014 (incorporated by reference to the Form 6-K of Cenovus Energy Inc. filed with the Securities and Exchange Commission on April 30, 2014) (File No. 1-34513).
	4.6	Management Proxy Circular of Cenovus Energy Inc., dated March 7, 2014, relating to the annual meeting of shareholders of Cenovus Energy Inc. held on April 30, 2014 (incorporated by reference to Cenovus Energy Inc.'s Form 6-K filed with the Securities and Exchange Commission on March 27, 2014) (File No. 1-34513).
	4.7	Supplementary Information — Oil and Gas Activities (unaudited) for the fiscal year ended December 31, 2013 (incorporated by reference to the Form 40-F of Cenovus Energy Inc. filed with the Securities and Exchange Commission on February 19, 2014) (File No. 1-34513).
	5.1	Consent of PricewaterhouseCoopers LLP.
	5.2†	Consent of Norton Rose Fulbright Canada LLP.
	5.3†	Consent of GLJ Petroleum Consultants Ltd.
	5.4†	Consent of McDaniel & Associates Consultants Ltd.
	6.1	Powers of Attorney (included on the signature page to this Registration Statement).
	7.1	Indenture, dated as of August 17, 2012, between Cenovus Energy Inc. and The Bank of New York Mellon, as Trustee (incorporated by reference to the Form 6-K of Cenovus Energy Inc. filed with the Securities and Exchange Commission on June 12, 2014) (File No. 1-34513).
	7.2	Statement of Eligibility of The Bank of New York Mellon on Form T-1.

†

To be filed by amendment.

QuickLinks

PART I INFORMATION REQUIRED TO BE DELIVERED TO OFFEREES OR PURCHASERS
ABOUT THIS PROSPECTUS
WHERE YOU CAN FIND MORE INFORMATION
FORWARD-LOOKING STATEMENTS
CENOVUS ENERGY INC.
USE OF PROCEEDS
DESCRIPTION OF DEBT SECURITIES
PART II INFORMATION NOT REQUIRED TO BE DELIVERED TO OFFEREES OR PURCHASERS
EXHIBITS
PART III UNDERTAKING AND CONSENT TO SERVICE OF PROCESS

Item 1. Undertaking
Item 2. Consent to Service of Process

SIGNATURES
POWERS OF ATTORNEY
AUTHORIZED REPRESENTATIVE
EXHIBITS INDEX