REGISTRATION RIGHTS AGREEMENT

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Exhibit 4.1

EXECUTION COPY

REGISTRATION RIGHTS AGREEMENT

by and among

Forest Oil Corporation
Forest Oil Permian Corporation

and

Banc of America Securities LLC
BNP Paribas Securities Corp.
Credit Suisse Securities (USA) LLC
Deutsche Bank Securities Inc.
J.P. Morgan Securities Inc.
TD Securities (USA) LLC
Scotia Capital (USA) Inc.
Wells Fargo Securities, LLC

Dated as of May 22, 2008

TABLE OF CONTENTS

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REGISTRATION RIGHTS AGREEMENT

        This Registration Rights Agreement (this " Agreement ") is made and entered into as of May 22, 2008, by and among Forest Oil Corporation, a New York corporation (the "Company"), Forest Oil Permian Corporation, a Delaware corporation (the "Guarantor") and Banc of America Securities LLC, BNP Paribas Securities Corp., Credit Suisse Securities (USA) LLC, Deutsche Bank Securities Inc., J.P. Morgan Securities Inc., TD Securities (USA) LLC, Scotia Capital (USA) Inc. and Wells Fargo Securities, LLC (collectively, the " Initial Purchasers "), who have agreed to purchase the Company's 7.25% Senior Notes due 2019 (the " Initial Notes ") fully and unconditionally guaranteed by the Guarantor (the " Guarantee ") pursuant to the Purchase Agreement (as defined below). The Initial Notes and the Guarantee are herein collectively referred to as the " Initial Securities ."

        This Agreement is made pursuant to the Purchase Agreement, dated May 19, 2008 (the " Purchase Agreement "), among the Company, the Guarantor and the Initial Purchasers (i) for the benefit of the Initial Purchasers and (ii) for the benefit of the Holders from time to time of the Initial Securities, including the Initial Purchasers. In order to induce the Initial Purchasers to purchase the Initial Securities, the Company has agreed to provide the registration rights set forth in this Agreement. The execution and delivery of this Agreement is a condition to the obligations of the Initial Purchasers set forth in Section 5(k) of the Purchase Agreement.

        The parties hereby agree as follows:

        SECTION 1.     Definitions.     As used in this Agreement, the following capitalized terms shall have the following meanings:

        Additional Interest:     As defined in Section 5(a) hereof.

        Advice:     As defined in the last paragraph of Section 6(c) hereof.

        Affiliates:     As defined in Rule 144 under the Securities Act.

        Agreement:     As defined in the preamble hereto.

        Blackout Period:     As defined in the last paragraph of Section 4(a) hereof.

        Broker-Dealer:     Any broker or dealer registered under the Exchange Act.

        Business Day:     As defined in the Indenture.

        Closing Date:     The date of this Agreement.

        Commission:     The Securities and Exchange Commission.

        Company:     As defined in the preamble hereto.

        Consummate:     The Exchange Offer shall be deemed "Consummated" for purposes of this Agreement upon the occurrence of (i) the filing and effectiveness under the Securities Act of the Exchange Offer Registration Statement relating to the Exchange Securities to be issued in the Exchange Offer, (ii) the maintenance of such Registration Statement continuously effective and the keeping of the Exchange Offer open for a period not less than the minimum period required pursuant to Section 3(b) hereof, and (iii) the delivery by the Company to the Registrar under the Indenture of Exchange Securities in the same aggregate principal amount as the aggregate principal amount of Initial Securities that were tendered by Holders thereof pursuant to the Exchange Offer.

        Exchange Act:     The Securities Exchange Act of 1934, as amended.

        Exchange Offer:     The Company's offer to the Holders of all outstanding Transfer Restricted Securities of the opportunity to exchange all such outstanding Transfer Restricted Securities held by such Holders for Exchange Securities in an aggregate principal amount equal to the aggregate principal amount of the Transfer Restricted Securities tendered in such exchange offer by such Holders.

        Exchange Offer Registration Statement:     The Registration Statement relating to the Exchange Offer, including the related Prospectus.

        Exempt Resales:     The transactions in which the Initial Purchasers propose to sell the Initial Securities to certain "qualified institutional buyers," as such term is defined in Rule 144A under the Securities Act and to certain non-U.S. persons pursuant to Regulation S under the Securities Act.

        Exchange Securities:     The 7.25% Senior Notes due 2019, of the same series under the Indenture as the Initial Notes, and the Guarantee related thereto, issued to Holders in exchange for Transfer Restricted Securities pursuant to this Agreement.

        FINRA:     The Financial Industry Regulatory Authority.

        Guarantee:     As defined in the preamble hereto.

        Holder:     As defined in Section 2(b) hereof.

        Indemnified Holder:     As defined in Section 8(a) hereof.

        Indenture:     The Indenture, dated as of June 6, 2007 by and among the Company, the Guarantor and the Trustee, pursuant to which the Securities are to be issued, as such Indenture is amended or supplemented from time-to-time in accordance with the terms thereof.

        Initial Purchasers:     As defined in the preamble hereto.

        Initial Notes:     As defined in the preamble hereto.

        Initial Placement:     The issuance and sale by the Company of the Initial Securities to the Initial Purchasers pursuant to the Purchase Agreement.

        Initial Securities:     As defined in the preamble hereto.

        Majority Holders:     The Holders of a majority of the aggregate principal amount of the outstanding Transfer Restricted Securities; provided, however , that whenever the consent or approval of Holders of a specified percentage of Transfer Restricted Securities is required hereunder, any Transfer Restricted Securities owned directly or indirectly by the Company or any of its Affiliates shall not be counted in determining whether such consent or approval was given by the Holders of such required percentage or amount; and provided, further , that if the Company shall issue any additional 7.25% Senior Notes due 2019 under the Indenture in a transaction not registered with the Commission prior (a) the date on which the restrictive legend on the Initial Securities has been removed and the Initial Securities are freely tradable (by Persons other than Affiliates of the Company) pursuant to Rule 144 under the Securities Act, (b) consummation of the Exchange Offer or (c) if applicable, the effectiveness of any Shelf Registration Statement, such additional 7.25% Senior Notes due 2019 and the Transfer Restricted Securities to which this Agreement relates shall be treated together as one class for purposes of determining whether the consent or approval of Holders of a specified percentage of Transfer Restricted Securities has been obtained.

        NASD:     The National Association of Securities Dealers, Inc.

        Person:     An individual, partnership, limited liability company, corporation, trust or unincorporated organization, or a government or agency or political subdivision thereof.

        Prospectus:     The prospectus included in a Registration Statement, as amended or supplemented by any prospectus supplement and by all other amendments thereto, including post-effective amendments, and all material incorporated by reference into such Prospectus.

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        Registration Default:     Any of the following events:

        (a)   the Initial Securities are not freely tradable (by Persons other than Affiliates of the Company) pursuant to Rule 144 under the Securities Act as of the 366th day after the Closing Date;

        (b)   the restrictive legend on the Initial Securities has not been removed as of the 366th day after the Closing Date; or

        (c)   after a Shelf Registration Statement is declared (or becomes automatically) effective (i) such Shelf Registration Statement thereafter ceases to be effective or (ii) such Shelf Registration Statement or the related Prospectus ceases to be usable in connection with resales of Transfer Restricted Securities during the periods specified herein (but excluding any Blackout Period) because either (A) any event occurs as a result of which the related Prospectus forming part of such Shelf Registration Statement would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein in the light of the circumstances under which they were made not misleading, (B) it shall be necessary to amend such Shelf Registration Statement or supplement the related Prospectus, to comply with the Securities Act or the Exchange Act or the respective rules thereunder or (C) such Shelf Registration Statement has expired before a replacement Shelf Registration Statement has become effective.

        Registration Statement:     Any registration statement of the Company relating to (a) an offering of Exchange Securities pursuant to the Exchange Offer or (b) the registration for resale of Transfer Restricted Securities pursuant to a Shelf Registration Statement, which is filed pursuant to the provisions of this Agreement, in each case, including the Prospectus.

        Securities:     The Initial Securities and the Exchange Securities.

        Securities Act:     The Securities Act of 1933, as amended.

        Shelf Registration Statement:     As defined in Section 4(a)(x) hereof.

        Trustee:     U.S. Bank National Association.

        Trust Indenture Act:     The Trust Indenture Act of 1939, as amended.

        Transfer Restricted Securities:     Each Initial Security, until the earliest to occur of (a) the date on which such Initial Security is exchanged in the Exchange Offer for an Exchange Security entitled to be resold to the public by the Holder thereof without complying with the prospectus delivery requirements of the Securities Act, (b) the date on which such Initial Security has been effectively registered under the Securities Act and disposed of in accordance with a Shelf Registration Statement, (c) the date on which the restrictive legend on such Initial Security has been removed and the Initial Security is freely tradable (by Persons other than Affiliates of the Company) pursuant to Rule 144 under the Securities Act, (d) the date on which such Initial Security is distributed to the public by a Broker-Dealer pursuant to the "Plan of Distribution" contemplated by the Exchange Offer Registration Statement (including delivery of the Prospectus contained therein) and (e) the date on which such Initial Security ceases to be outstanding for purposes of the Indenture.

        Underwritten Registration or Underwritten Offering:     A registration in which securities of the Company are sold to an underwriter for reoffering to the public.

        SECTION 2.     Securities Subject to this Agreement.     

        (a)     Transfer Restricted Securities.     The Transfer Restricted Securities are entitled to the benefits of this Agreement.

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        (b)     Holders of Transfer Restricted Securities.     A Person is deemed to be a holder of Transfer Restricted Securities (each, a " Holder ") whenever such Person owns Transfer Restricted Securities.

        SECTION 3.     Registered Exchange Offer.     

        (a)   If the restrictive legend on the Initial Securities has not been removed and the Initial Securities are not freely tradable pursuant to Rule 144 under the Securities Act (by Persons other than Affiliates of the Company) as of the 366th day after the Closing Date, each of the Company and the Guarantor shall, at their cost, (i) cause to be filed with the Commission, a Registration Statement under the Securities Act relating to the Exchange Securities (other than Transfer Restricted Securities acquired by any Broker-Dealer directly from the Company) and the Exchange Offer, (ii) use commercially reasonable efforts (which shall include the filing of all necessary amendments to such Registration Statement) to cause such Registration Statement to be declared effective by the Commission and (iii) upon the effectiveness of such Registration Statement, promptly commence the Exchange Offer. The Exchange Offer shall be on the appropriate form permitting registration of the Exchange Securities to be offered in exchange for the Transfer Restricted Securities (other than Transfer Restricted Securities acquired by any Broker-Dealer directly from the Company) and to permit resales of Initial Securities held by Broker-Dealers as contemplated by Section 3(c) hereof. Neither the Company nor the Guarantor shall have any obligation under this Agreement to file a Registration Statement with the Commission or commence an Exchange Offer or any other offer pursuant to this Agreement if there are no Transfer Restricted Securities as of the 366th day after the Closing Date.

        (b)   If the Company and the Guarantor are required to commence the Exchange Offer pursuant to Section 3(a) above, the Company and the Guarantor shall cause the Exchange Offer Registration Statement to be effective continuously and shall keep the Exchange Offer open for a period of not less than 20 Business Days (or longer if required under applicable law) after the date that notice of the Exchange Offer is mailed to Holders. The Company shall cause the Exchange Offer to comply with all applicable federal and state securities laws. No securities other than the Exchange Securities shall be included in the Exchange Offer Registration Statement.

        (c)   If the Company and the Guarantor are required to commence the Exchange Offer pursuant to Section 3(a) above, the Company shall indicate in a "Plan of Distribution" section contained in the Prospectus forming a part of the Exchange Offer Registration Statement that any Broker-Dealer who holds Initial Securities that are Transfer Restricted Securities that were acquired for its own account as a result of market-making activities or other trading activities (other than Transfer Restricted Securities acquired directly from the Company) may exchange such Initial Securities pursuant to the Exchange Offer; however, such Broker-Dealer may be deemed to be an "underwriter" within the meaning of the Securities Act and must, therefore, deliver a prospectus meeting the requirements of the Securities Act in connection with any resales of the Exchange Securities received by such Broker-Dealer in the Exchange Offer, which prospectus delivery requirement may be satisfied by the delivery by such Broker-Dealer of the Prospectus contained in the Exchange Offer Registration Statement. Such "Plan of Distribution" section shall also contain all other information with respect to such resales by Broker-Dealers that the Commission may require in order to permit such resales pursuant thereto, but such "Plan of Distribution" shall not name any such Broker-Dealer or disclose the amount of Initial Securities held by any such Broker-Dealer except to the extent required by the Commission.

        If the Company and the Guarantor are required to commence the Exchange Offer pursuant to Section 3(a) above, each of the Company and the Guarantor shall use commercially reasonable efforts to keep the Exchange Offer Registration Statement continuously effective, supplemented and amended as required by the provisions of Section 6(c) hereof to the extent necessary to ensure that it is available for resales of Initial Securities acquired by Broker-Dealers for their own accounts as a result of market-making activities or other trading activities, and to ensure that it conforms with the requirements of this Agreement, the Securities Act and the policies, rules and regulations of the Commission as

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announced from time to time, for a period ending on the earlier of (i) 180 days after the Consummation of the Exchange Offer and (ii) the date on which a Broker-Dealer is no longer required to deliver a prospectus in connection with market-making or other trading activities.

        If the Company and the Guarantor are required to commence the Exchange Offer pursuant to Section 3(a) above, the Company shall provide sufficient copies of the latest version of such Prospectus to Broker-Dealers promptly upon request at any time during such 180-day (or shorter as provided in the foregoing sentence) period in order to facilitate such resales.

        SECTION 4.     Shelf Registration.     

        (a)     Shelf Registration.     

        If (i) because of any change in law or in applicable interpretations thereof by the staff of the Commission, the Company is not permitted to effect an Exchange Offer that is required by Section 3 hereof, (ii) for any reason the Exchange Offer is required by Section 3 hereof to be but is not Consummated within one year and 90 days of the Closing Date, (iii) any Initial Purchaser so requests with respect to the Initial Securities not eligible to be exchanged for Exchange Securities in any Exchange Offer required by Section 3 hereof and held by it following Consummation of such Exchange Offer or (iv) any Holder (other than a Broker-Dealer who holds Transfer Restricted Securities that were acquired for its own account as a result of market-making activities or other trading activities) is not eligible to participate in any Exchange Offer required by Section 3 hereof or, in the case of any Holder (other than a Broker-Dealer who holds Transfer Restricted Securities that were acquired for its own account as a result of market-making activities or other trading activities) that participates in any such Exchange Offer, such Holder does not receive freely tradable Exchange Securities on the date of the exchange, then the Company and the Guarantor shall, at their cost:

        (x)   promptly cause to be filed a shelf registration statement pursuant to Rule 415 under the Securities Act, which may be an amendment to the Exchange Offer Registration Statement (in either event, the " Shelf Registration Statement "), which Shelf Registration Statement shall provide for resales of all Transfer Restricted Securities the Holders of which shall have provided the information required pursuant to Section 4(b) hereof; and

        (y)   use commercially reasonable efforts to cause such Shelf Registration Statement to be declared effective by the Commission on or before the 90th day after the date on which the filing obligation arises.

        Each of the Company and the Guarantor shall use commercially reasonable efforts to keep such Shelf Registration Statement continuously effective, supplemented and amended as required by the provisions of Sections 6(b) and (c) hereof to the extent necessary to ensure that it is available for resales of Initial Securities by the Holders of Transfer Restricted Securities entitled to the benefit of this Section 4(a) and to ensure that it conforms with the requirements of this Agreement, the Securities Act and the policies, rules and regulations of the Commission as announced from time to time, for a period of at least one year following the effective date of the Shelf Registration Statement or such shorter period that will terminate when all the Initial Securities covered by such Shelf Registration Statement (A) have been sold pursuant to such Shelf Registration Statement or (B) may be sold (by Persons who are not Affiliates of the Company) without a restrictive legend pursuant to Rule 144 under the Securities Act or any successor rule thereof. Each of the Company and the Guarantor shall be deemed not to have used commercially reasonable efforts to keep the Shelf Registration Statement effective during the requisite period if any of the Company or the Guarantor voluntarily takes any action that would result in Holders of Transfer Restricted Securities covered thereby not being able to offer and sell such Transfer Restricted Securities during that period, unless (X) such action is required by applicable law; or (Y) such action is taken by any of the Company or Guarantor in good faith and for valid business reasons (not including avoidance of the Company or the Guarantor obligations

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hereunder) including, but not limited to, the acquisition or divestiture of assets, so long as the Company and the Guarantor promptly thereafter comply with the requirements of the last paragraph of Section 6(c) hereof (the period during which the Shelf Registration Statement is not available under clauses (X) or (Y) above, the " Blackout Period "). The Blackout Period shall not exceed 45 days in any three-month period or 90 days in any twelve-month period.

        (b)     Provision by Holders of Certain Information in Connection with the Shelf Registration Statement.     No Holder of Transfer Restricted Securities may include any of its Transfer Restricted Securities in any Shelf Registration Statement pursuant to this Agreement unless and until such Holder furnishes to the Company in writing, within 20 Business Days after receipt of a request therefor, such information as the Company may reasonably request for use in connection with any Shelf Registration Statement or Prospectus or preliminary Prospectus included therein. Each Holder as to which any Shelf Registration Statement is being effected agrees to furnish promptly to the Company all information required to be disclosed in order to make the information previously furnished to the Company by such Holder not materially misleading.

        SECTION 5.     Additional Interest.     

        (a)   If any Registration Default shall occur, the Company hereby agrees that the interest rate borne by the Transfer Restricted Securities shall be increased by 0.25% per annum during the 90-day period immediately following the occurrence of any Registration Default and shall increase by 0.25% per annum at the end of each subsequent 90-day period, but in no event shall such increase exceed 1.00% per annum. Such additional interest to be paid pursuant to a Registration Default as set forth in this Section 5 is herein referred to as " Additional Interest ."

        (b)   Registration Defaults shall be cured on the date that (i) the Initial Securities are freely tradable (by Persons other than Affiliates of the Company) pursuant to Rule 144 under the Securities Act and the restrictive legend on the Initial Securities has been removed, (ii) the Exchange Offer has been effected (provided that this clause (ii) shall not cure a Registration Default if a Shelf Registration Statement is required to be filed pursuant to clause (i), (iii) or (iv) of the first paragraph of Section 4(a)) or (iii) a Shelf Registration Statement is declared (or automatically becomes) effective under the Securities Act, unless subsequent to the date it was last declared effective it fails to remain effective or usable for the time period contemplated by Section 4(a) after taking into account all other periods during which such Shelf Registration Statement was effective. Following the cure of all Registration Defaults relating to any particular Transfer Restricted Securities in accordance with this Section 5(b), the interest rate borne by the relevant Transfer Restricted Securities will be reduced to the original interest rate borne by such Transfer Restricted Securities; provided, however, that, if after any such reduction in interest rate, a different Registration Default occurs, the interest rate borne by the relevant Transfer Restricted Securities shall again be increased pursuant to the foregoing provisions. The Company shall not be required to pay Additional Interest for more than one Registration Default at any given time.

        (c)   All Additional Interest accrued pursuant to this Section 5 shall be paid in the manner provided for in the Indenture. All Additional Interest shall be in addition to any other interest payable from time to time with respect to the Initial Securities and the Exchange Securities. All obligations of the Company and the Guarantor set forth in Section 5(a) that are outstanding with respect to any Transfer Restricted Security at the time such security ceases to be a Transfer Restricted Security shall survive until such time as all such obligations with respect to such security shall have been satisfied in full.

        SECTION 6.     Registration Procedures.     

        (a)     Exchange Offer Registration Statement.     In connection with the Exchange Offer, the Company and the Guarantor shall comply with all of the provisions of Section 6(c) hereof, shall use commercially

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reasonable efforts to effect such exchange to permit the sale of Transfer Restricted Securities being sold in accordance with the intended method or methods of distribution thereof. As a condition to its participation in the Exchange Offer pursuant to the terms of this Agreement, each Holder of Transfer Restricted Securities shall furnish, upon the request of the Company, prior to the Consummation thereof, a written representation to the Company (which may be contained in the letter of transmittal contemplated by the Exchange Offer Registration Statement) to the effect that (A) it is not an affiliate (within the meaning of Rule 405 under the Securities Act) of any of the Company or the Guarantor, (B) it is not engaged in, and does not intend to engage in, and has no arrangement or understanding with any Person to participate in, a distribution of the Exchange Securities to be issued in the Exchange Offer and (C) it is acquiring the Exchange Securities in its ordinary course of business. In addition, all such Holders of Transfer Restricted Securities shall otherwise cooperate in the Company's preparations for the Exchange Offer. Each Holder hereby acknowledges and agrees that any Broker-Dealer and any such Holder using the Exchange Offer to participate in a distribution of the securities to be acquired in the Exchange Offer (1) could not under Commission policy as in effect on the date of this Agreement rely on the position of the Commission enunciated in Morgan Stanley and Co., Inc. (available June 5, 1991) and Exxon Capital Holdings Corporation (available May 13, 1988), as interpreted in the Commission's letter to Shearman & Sterling dated July 2, 1993, and similar no-action letters, and (2) must comply with the registration and prospectus delivery requirements of the Securities Act in connection with a secondary resale transaction and that such a secondary resale transaction should be covered by an effective registration statement containing the selling security holder information required by Item 507 or 508, as applicable, of Regulation S-K if the resales are of Exchange Securities obtained by such Holder in exchange for Initial Securities acquired by such Holder directly from the Company.

        (b)     Shelf Registration Statement.     In connection with any Shelf Registration Statement, each of the Company and the Guarantor shall comply with all the provisions of Section 6(c) hereof and shall use commercially reasonable efforts to effect such registration to permit the sale of the Transfer Restricted Securities being sold in accordance with the intended method or methods of distribution thereof, and pursuant thereto each of the Company and the Guarantor will as expeditiously as possible prepare and file with the Commission a Registration Statement relating to the registration on any appropriate form under the Securities Act, which form shall be available for the sale of the Transfer Restricted Securities in accordance with the intended method or methods of distribution thereof.

        (c)     General Provisions.     In connection with any Registration Statement and any Prospectus required by this Agreement to permit the sale or resale of Transfer Restricted Securities (including, without limitation, any Registration Statement and the related Prospectus required to permit resales of Initial Securities by Broker-Dealers), each of the Company and the Guarantor shall:

        (i)    use commercially reasonable efforts to keep such Registration Statement continuously effective and provide all requisite financial statements (including, if required by the Securities Act or any regulation thereunder, financial statements of the Guarantor) for the period specified in Section 3 or 4 hereof, as applicable; upon the occurrence of any event that would cause any such Registration Statement or the Prospectus contained therein (A)