EXHIBIT 2.2 AGREEMENT AND PLAN OF REORGANIZATION BY AND BETWEEN USX CORPORATION AND UNITED STATES STEEL LLC DATED AS OF JULY 31, 2001

EXHIBIT 2.2

AGREEMENT AND PLAN OF REORGANIZATION

BY AND BETWEEN

USX CORPORATION

AND

UNITED STATES STEEL LLC

DATED AS OF

JULY 31, 2001

TABLE OF CONTENTS

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ii

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Annex A

AGREEMENT AND PLAN OF REORGANIZATION

        Agreement and Plan of Reorganization ("Agreement"), dated as of July 31, 2001, by and between USX Corporation, a Delaware corporation, to be renamed "Marathon Oil Corporation"("USX"), and United States Steel LLC, a Delaware limited liability company and wholly owned subsidiary of USX, to be renamed "United States Steel Corporation" ("SteelCo").

W I T N E S S E T H:

        Whereas, USX is a diversified company principally engaged in the energy business and the steel business;

        Whereas, pursuant to the Restated Certificate of Incorporation of USX (the "Restated Certificate"), the businesses of USX are divided between two groups, the Marathon Group and the U.S. Steel Group (each, as defined in the Restated Certificate);

        Whereas, USX has outstanding two classes of common stock, USX-Marathon Group Common Stock, par value $1.00 per share ("Marathon Group Shares"), which is intended to reflect the performance of the Marathon Group, and USX-U.S. Steel Group Common Stock, par value $1.00 per share ("U.S. Steel Group Shares"), which is intended to reflect the performance of the U.S. Steel Group;

        Whereas, prior to the date hereof, USX implemented a holding company structure by merging the then-existing USX Corporation, a Delaware corporation ("Old USX"), with and into SteelCo, with SteelCo continuing as the surviving entity and a wholly owned subsidiary of USX (the "HoldCo Merger"), so that immediately following the effective time of the HoldCo Merger, USX became a holding company that owns all of the outstanding equity of Marathon Oil Company (which owns and operates the business of the Marathon Group) and of SteelCo (which owns and operates the business of the U.S. Steel Group);

        Whereas, the board of directors of SteelCo has determined that it is advisable and in the best interests of SteelCo and its sole member to convert SteelCo into a Delaware corporation named "United States Steel Corporation" (the "U.S. Steel Conversion"), subject to the terms and conditions hereof, and pursuant to Section 265 of the General Corporation Law of the State of Delaware (as amended from time to time, the "DGCL") and Section 18-216 of the Delaware Limited Liability Company Act (as amended from time to time, the "DLLCA"), effective at the Separation Effective Time (as defined herein);

        Whereas, the board of directors of USX (the "Board") has determined that it is advisable and in the best interests of USX and its stockholders to separate the respective businesses of the Marathon Group and the U.S. Steel Group following the U.S. Steel Conversion, by merging USX Merger Corporation, a Delaware corporation and a wholly owned subsidiary of USX ("Merger Sub"), with and into USX, subject to the terms and conditions hereof, and pursuant to Section 251 of the DGCL (the "Separation Merger"), with USX continuing as the surviving corporation, so that immediately following the Separation Effective Time, SteelCo (to be renamed United States Steel Corporation) shall own and operate the business of the U.S. Steel Group and shall be wholly owned by the holders of the U.S. Steel Group Shares immediately prior to the Separation Effective Time, and the business of the Marathon Group shall be owned and operated by USX (to be renamed Marathon Oil Corporation), which shall be a separate and independent entity from SteelCo and shall be wholly owned by the holders of the Marathon Group Shares immediately prior to the Separation Effective Time (the "Separation");

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        Whereas, the Board has received the opinions of Credit Suisse First Boston Corporation and Salomon Smith Barney (collectively, the "Financial Advisors"), financial advisors to the Board, that, as of the date hereof, the financial effects, taken as a whole, of the transactions contemplated by this Agreement are fair, from a financial point of view, to the holders of the Marathon Group Shares and the holders of the U.S. Steel Group Shares;

        Whereas, the Board has received an opinion of American Appraisal Associates, Inc. that, with respect to USX prior to the Separation and with respect to each of Marathon Oil Corporation and United States Steel Corporation both immediately before and after, and giving effect to, the Separation, the fair value of its aggregate assets exceed its total liabilities; the present fair saleable value of its aggregate assets exceeds the probable liability on its debts as they become absolute and matured; it will be able to pay its debts and other liabilities as they mature; and it will not have unreasonably small capital with which to conduct its business, as presently conducted and as proposed to be conducted;

        Whereas, the Board has determined that the Separation Merger will, among other things, allow Marathon Oil Corporation and United States Steel Corporation to focus on their core businesses and make critical acquisitions and investments needed to grow their respective businesses and will enhance stockholder value for all of USX's stockholders through the creation of two strong, independent companies;

        Whereas, the Board has, in light of and subject to the terms and conditions set forth herein, (i) determined that the Separation Merger is advisable and in the best interests of USX and the holders of each of the Marathon Group Shares and the U.S. Steel Group Shares, (ii) approved and declared the advisability of this Agreement and the transactions contemplated hereby and (iii) determined to recommend that the common stockholders of USX vote to adopt this Agreement;

        Whereas, the respective boards of directors of SteelCo and Merger Sub have approved and declared the advisability of this Agreement and the transactions contemplated by this Agreement, including, without limitation, the U.S. Steel Conversion and the Separation Merger (collectively, the "Transactions"), and USX, as the sole stockholder of Merger Sub, has adopted this Agreement;

        Whereas, it is the intention of the parties hereto that the transactions contemplated by this Agreement shall be a tax-free transaction under Section 355 of the Internal Revenue Code of 1986, as amended (the "Code"), and the rules and regulations promulgated thereunder; and

        Whereas, the parties hereto desire to make certain covenants and agreements and to allocate certain assets, liabilities and obligations in connection with the U.S. Steel Conversion, the Separation Merger and the other Transactions contemplated by this Agreement and to prescribe various conditions to the Transactions.

        Now, Therefore, in furtherance of the foregoing and in consideration of the mutual promises and undertakings contained herein and in any other document executed in connection with this Agreement, the parties agree as follows:

ARTICLE I

Definitions

        Section 1.1 General. For the purposes of this Agreement, the following terms shall have the meanings set forth below:

•         (a)   "Action" shall mean any action, claim (whether or not filed), suit, arbitration, inquiry, demand, proceeding or investigation.

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•         (b)   "Affiliate" shall mean, with respect to any specified Person, any other Person directly or indirectly controlling, controlled by, or under common control with, such specified Person; provided, however, that for purposes of this Agreement, from and after the Separation Effective Time, neither SteelCo nor any of its Subsidiaries shall be deemed to be an Affiliate of USX or any of its Subsidiaries, and neither USX nor any of its Subsidiaries shall be deemed to be an Affiliate of SteelCo or any of its Subsidiaries.

          (c)   "Applicable Law" shall mean, with respect to any Person, all statutes, laws, ordinances, rules, orders and regulations of any Governmental Authority applicable to such Person and its business, properties and assets.

          (d)   "Confidential Information" shall mean, with respect to either Group, Information regarding a member of such Group, or any of its operations, assets or Liabilities (whether in documents or stored in any other form or known to its employees or agents) which is not generally available to the public (other than as a result of a wrongful disclosure).

          (e)   "Contract" shall mean any contract, agreement, lease, license, sales order, purchase order, instrument or other commitment, written or oral.

          (f)    "Disclosure Letter" shall mean the letter, dated as of the date hereof, delivered by USX to the other parties hereto, as the same may be amended or supplemented from time to time.

          (g)   "Employee Arrangements" shall mean all employment or consulting agreements or arrangements, all severance or change in control agreements or arrangements and all other agreements or arrangements with respect to the employment and termination of employment of any employee, officer or director.

          (h)   "Employee Incentive Plans" shall mean all incentive compensation, stock award, stock option or stock purchase plans and equity compensation arrangements.

          (i)    "Exchange Act" shall mean the Securities Exchange Act of 1934, as amended, together with the rules and regulations promulgated thereunder.

          (j)    "Governmental Authority" shall mean any foreign, federal, state or local government, court, agency or commission or other governmental or regulatory body or authority.

          (k)   "Group" shall mean the Marathon Group and/or the U.S. Steel Group, as the case may be.

          (l)    "HoldCo Reorganization Agreement" shall mean the Holding Company Reorganization Agreement, dated as of July 1, 2001, among USX Corporation, USX HoldCo, Inc. and United States Steel LLC.

          (m)  "Indemnifiable Losses" shall mean, with respect to any claim by an Indemnified Party for indemnification under this Agreement, any and all damages, losses, deficiencies, Liabilities, obligations, penalties, judgments, settlements, claims, payments, fines, interest, costs and expenses (including, without limitation, the costs and expenses of any and all Actions, demands, assessments, judgments, settlements and compromises relating thereto and the reasonable costs and expenses of attorneys', accountants', consultants' and other professionals' fees and expenses incurred in the investigation or defense thereof or the enforcement of rights thereunder), including direct, consequential, exemplary, special and punitive damages and lost profits.

          (n)   "Indemnified Party" shall mean any Person that is seeking indemnification from an Indemnifying Party pursuant to the provisions of this Agreement.

          (o)   "Indemnifying Party" shall mean any party hereto from which any Indemnified Party is seeking indemnification pursuant to the provisions of this Agreement.

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          (p)   "Information" shall mean all records, books, Contracts, instruments, computer data and other data and information.

          (q)   "Insurance Arrangements" shall mean insurance policies and insurance Contracts of any kind, including, without limitation, primary and excess policies, commercial general liability policies, automobile policies, product liability policies, directors' and officers' liability policies, fiduciary liability policies, workers' compensation policies, and self- insurance programs and captive insurance company arrangements, together with the rights, benefits and privileges thereunder.

          (r)   "Insurance Proceeds" shall mean those monies received by an insured from an Insurer or paid by an Insurer on behalf of an insured, in either case net of any applicable premium adjustment, retrospectively rated premium, deductible, retention or cost of reserve paid or held by or for the benefit of such insured.

          (s)   "Insurer" shall mean a third-party insurance carrier.

          (t)    "Joint Insurance Arrangements" shall mean the Insurance Arrangements of USX existing at the Separation Effective Time and/or prior thereto that are (i) owned or maintained by or on behalf of USX or any of its predecessors and that relate to both (a) the U.S. Steel Group assets, business and/or Liabilities and (b) the Marathon Group assets, business and/or Liabilities and (ii) listed in Section 1.1(t) of the Disclosure Letter.

          (u)   "Liability" shall mean, with respect to any Person, except as otherwise expressly provided herein, any direct or indirect liability (whether absolute, accrued or unaccrued, contingent, liquidated or unliquidated, matured or unmatured or known or unknown), indebtedness, obligation, indemnification obligation, expense, claim, deficiency, guarantee or endorsement of or by such Person (including, without limitation, those arising under any Applicable Law or Action or under any award of any court, tribunal or arbitrator of any kind, and those arising under any Contract or undertaking).

          (v)   "Litigation Matters" shall mean actual, threatened or future Actions that have been or may be asserted against, or otherwise adversely affect, any member of either Group.

          (w)  "Marathon" shall mean Marathon Oil Company, an Ohio corporation and a wholly owned subsidiary of USX.

          (x)   "Marathon Employees" shall mean any Person employed by Marathon or its Subsidiaries.

          (y)   "Marathon Group Option" shall mean each option to purchase Marathon Group Shares granted under the USX Corporation 1990 Stock Plan.

          (z)   "Marathon Group SAR" shall mean each stock appreciation right of USX relating to Marathon Group Shares granted under the USX Corporation 1990 Stock Plan.

          (aa) "Pension Assets" shall mean the assets of the USS Non-Union Plan.

          (bb) "Person" or "Persons" shall mean and include any individual, partnership, joint venture, corporation, association, joint stock company, limited liability company, trust, unincorporated organization or similar entity.

          (cc) "Privileged Information" shall mean, with respect to either Group, Information regarding a member of such Group, or any of its operations, assets or Liabilities (whether in documents or stored in any other form or known to its employees or agents) that is or may be protected from disclosure pursuant to the attorney-client privilege, the work-product doctrine or other applicable privileges.

          (dd) "Representative" shall mean, with respect to any Person, any of such Person's directors, officers, employees, agents, consultants, advisors, accountants, attorneys and representatives.

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          (ee) "SEC" shall mean the United States Securities and Exchange Commission.

          (ff) "Securities Act" shall mean the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

          (gg) "Separation Documents" shall mean this Agreement, the Tax Sharing Agreement, the Transition Services Agreement, the Financial Matters Agreement, the Insurance Assistance Agreement, the License Agreement, the Fairfield Caster Sublease and documents, schedules, exhibits and appendices attached hereto or thereto or delivered pursuant hereto or thereto, including, without limitation, the Disclosure Letter, the deeds, lease assignments and assumptions, leases, subleases and sub-subleases, and the supplemental and other agreements and instruments relative thereto.

          (hh) "Stockholder Rights Plan" shall mean the Rights Agreement, dated as of September 28, 1999, between Old USX and ChaseMellon Shareholder Services, L.L.C., as Rights Agent, as amended from time to time.

          (ii) "Subsidiary" shall mean, with respect to any Person, each corporation, partnership, limited liability company or other legal entity of which such Person owns, either directly or indirectly, 50% or more of the stock or other equity interests the holders of which are generally entitled to vote for the election of the board of directors or similar governing body of such corporation, partnership, limited liability company or other legal entity.

          (jj) "Tax" or "Taxes" shall mean all taxes, charges, fees, imposts, levies or other assessments, including, without limitation, all net income, gross receipts, capital, sales, use, ad valorem, value added, transfer, franchise, profits, inventory, capital stock, license, withholding, payroll, employment, social security, unemployment, excise, severance, stamp, occupation, property and estimated taxes, customs duties, fees, assessments and charges of any kind whatsoever, together with any interest and any penalties, fines, additions to tax or additional amounts imposed by any taxing authority (domestic or foreign) and shall include any transferee liability in respect of Taxes.

          (kk) "Trademarks" shall mean all registered and unregistered trademarks, service marks, service names, trade styles and trade names (including, without limitation, trade dress and other names, marks and slogans) and all associated goodwill and all applications for any of the foregoing, together with all rights to use any of the foregoing.

          (ll) "U.S. Steel Group Option" shall mean each option to purchase U.S. Steel Group Shares granted under the USX Corporation 1990 Stock Plan.

          (mm) "U.S. Steel Group SAR" shall mean each stock appreciation right of USX Corporation relating to U.S. Steel Group Shares granted under the USX Corporation 1990 Stock Plan.

          (nn) "USX Corporate Assets" shall mean assets owned or leased by USX at the Separation Effective Time and which are not designated in the accounting records of USX as being solely attributable to either Group. Without limiting the foregoing, USX Corporate Assets shall include those assets listed in Section 1.1(nn) of the Disclosure Letter.

          (oo) "USX Corporate Employees" shall mean all persons employed by USX or Old USX at any time on or after May 1991 up to the Separation Effective Time who are or were designated in the payroll records of USX or Old USX as employees of USX or Old USX headquarters.

        Section 1.2 Other Definitional Provisions.

•         (a)   The words "hereof", "herein", "hereunder" and words of similar import, when used in this Agreement, shall refer to this Agreement as a whole and not to any particular provision of this Agreement.

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•         (b)   The terms defined in the singular shall have a comparable meaning when used in the plural, and vice versa.

          (c)   The terms "dollars" and "$" shall mean United States dollars.

ARTICLE II

Terms Defined Elsewhere in This Agreement

        For the purposes of this Agreement, the following terms have the meanings set forth on the pages indicated:

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ARTICLE III

U.S. Steel Conversion

        Section 3.1 U.S. Steel Conversion. At the Separation Effective Time, upon the terms and subject to the conditions of this Agreement and in accordance with Section 18-216 of the DLLCA and

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Section 265 of the DGCL, SteelCo shall be converted into a Delaware corporation named United States Steel Corporation ("United States Steel Corporation").

        Section 3.2 Effective Time of U.S. Steel Conversion. Subject to the provisions of this Agreement, the parties shall cause the U.S. Steel Conversion to be consummated by filing (a) a certificate of conversion (the "Certificate of Conversion") in accordance with Section 265 of the DGCL and (b) a certificate of incorporation for United States Steel Corporation, substantially in the form of Appendix A hereto (the "U.S. Steel Charter") with the Secretary of State of the State of Delaware, each executed in accordance with the relevant provisions of the DGCL and the DLLCA, as soon as practicable on or after the Conversion Closing Date (as defined in Section 3.3 below). The U.S. Steel Conversion shall become effective upon such filings or at such time thereafter as is provided in the Certificate of Conversion, which shall be at the Separation Effective Time (the "Conversion Effective Time").

        Section 3.3 Closing of the U.S. Steel Conversion. The closing of the U.S. Steel Conversion (the "Conversion Closing") shall take place at the offices of USX, 600 Grant Street, Pittsburgh, Pennsylvania 15219-4776, at 10:00 a.m. (local time), on a date to be specified by the parties (the "Conversion Closing Date"), which shall be on the Separation Closing Date, unless the parties agree to another time, date or place in writing.

        Section 3.4 Effects of the U.S. Steel Conversion. The U.S. Steel Conversion shall have the effects set forth in Section 265 of the DGCL. Without limiting the generality of the foregoing, and subject thereto, from and after the Conversion Effective Time, United States Steel Corporation shall be a corporation governed by all of the provisions of the DGCL; provided that the U.S. Steel Conversion shall not affect any of the obligations or Liabilities of SteelCo incurred prior to the Conversion Effective Time, including, without limitation, any obligations of SteelCo arising under this Agreement. SteelCo hereby acknowledges and agrees that United States Steel Corporation shall remain responsible for all of such obligations and Liabilities following the Conversion Effective Time.

        Section 3.5 Certificate of Incorporation; By-laws.

•         (a)   The U.S. Steel Charter shall be the certificate of incorporation of United States Steel Corporation from and after the Conversion Effective Time, until thereafter amended as provided by the DGCL and such U.S. Steel Charter.

          (b)   The by-laws of United States Steel Corporation, substantially in the form of Appendix B hereto (the "U.S. Steel By-laws"), shall be the by-laws of United States Steel Corporation from and after the Conversion Effective Time, until thereafter amended in accordance with its terms and as provided by the DGCL and the U.S. Steel Charter.

        Section 3.6 Directors. The directors of SteelCo immediately prior to the Conversion Effective Time shall be the directors of United States Steel Corporation from and after the Conversion Effective Time, and shall hold office until their respective successors are duly elected or appointed and qualified in the manner provided for in the U.S. Steel Charter and the U.S. Steel By-laws, or as otherwise provided by Applicable Law.

        Section 3.7 Officers. The officers of SteelCo immediately prior to the Conversion Effective Time shall be the officers of United States Steel Corporation from and after the Conversion Effective Time, and shall hold office until the earlier of their resignation or removal or until their successors are duly elected or appointed and qualified in the manner provided in the U.S. Steel Charter and the U.S. Steel By-laws, or as otherwise provided by Applicable Law.

        Section 3.8 Conversion of Securities. At the Conversion Effective Time, by virtue of the U.S. Steel Conversion and without any action on the part of any holder thereof, all of the limited liability company interests of SteelCo ("SteelCo Interests") issued and outstanding immediately prior to the

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Conversion Effective Time shall be converted into and thereafter represent an aggregate of one hundred (100) duly issued, fully paid and nonassessable shares of common stock, par value $1.00 per share, of United States Steel Corporation.

        Section 3.9 Further Actions. If, at any time after the Conversion Effective Time, United States Steel Corporation shall determine or be advised that any deeds, bills of sale, assignments, assurances or any other actions or things are necessary or desirable to vest, perfect or confirm of record or otherwise in United States Steel Corporation its right, title or interest in, to or under any of the rights, properties or assets of SteelCo acquired or to be acquired by United States Steel Corporation as a result of, or in connection with, the U.S. Steel Conversion or otherwise to carry out this Agreement, the officers and directors of United States Steel Corporation shall be authorized to execute and deliver, in the name and on behalf of either United States Steel Corporation or SteelCo, all such deeds, bills of sale, instruments of conveyance, assignments and assurances and to take and do, in the name and on behalf of United States Steel Corporation, SteelCo or otherwise, all such other actions and things as may be necessary or desirable to vest, perfect or confirm any and all right, title and interest in, to and under such rights, properties or assets in United States Steel Corporation or otherwise to carry out this Agreement.

ARTICLE IV

Actions to be Taken Prior to the Separation

        Section 4.1 Stockholders' Meeting. USX, acting through its Board, and subject to the right of the Board to terminate this Agreement and abandon the Transactions pursuant to Section 14.1 hereof, shall take all actions necessary in accordance with Applicable Law and USX's certificate of incorporation and by-laws to:

•         (a)   call, give notice of, convene and hold a meeting of its stockholders (the "Stockholders' Meeting"), as promptly as practicable following the date of this Agreement, for the purpose of obtaining (i) the approval and adoption of this Agreement by the stockholders of USX, (ii) the approval of the United States Steel Corporation 2002 Stock Plan (as hereinafter defined) by the stockholders of USX and (iii) the approval of the United States Steel Incentive Plan (as hereinafter defined) by the stockholders of USX;

          (b)   prepare and file with the SEC, as promptly as practicable following the date of this Agreement, revised preliminary proxy material under the Exchange Act relating to the Stockholders' Meeting and a registration statement on Form S-4, in which such proxy material shall be included, as a prospectus (the "Form S-4") registering under the Securities Act the issuance of the shares of United States Steel Common Stock (as hereinafter defined) to holders of U.S. Steel Group Shares in the Separation Merger, and use its reasonable efforts to obtain and furnish the information required to be included in such Form S-4 and proxy material and respond promptly to any comments made by the SEC and its staff with respect to the Form S-4 and preliminary proxy material and cause the Form S-4 to be declared effective under the Securities Act and cause a definitive proxy statement relating to the Stockholders' Meeting (such proxy statement, together with any and all amendments or supplements thereto, the "Proxy Statement") to be mailed to USX stockholders at the earliest practicable time;

          (c)   include in the Proxy Statement the recommendation of the Board that stockholders of USX vote in favor of the adoption of this Agreement, approval of the United States Steel Corporation 2002 Stock Plan and approval of the United States Steel Incentive Plan; and

          (d)   use its reasonable efforts to solicit from USX stockholders proxies in favor of the adoption of this Agreement, approval of the United States Steel Corporation 2002 Stock Plan and approval of the United States Steel Incentive Plan, and take all other actions necessary or

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  advisable to secure, at the Stockholders' Meeting, (x) the affirmative vote of (i) the holders of a majority of the outstanding Marathon Group Shares (voting as a separate class, with each Marathon Group Share having one vote), (ii) the holders of a majority of the outstanding U.S. Steel Group Shares (voting as a separate class, with each U.S. Steel Group Share having one vote), and (iii) the holders of a majority of the outstanding Marathon Group Shares and U.S. Steel Group Shares (voting together as a single class, with each U.S. Steel Group Share having the number of a votes, as determined pursuant to the terms of the Restated Certificate, and each Marathon Group Share having one vote) in favor of the adoption of this Agreement (the "USX Stockholder Approval") and (y) the affirmative vote of (i) a majority of the votes cast at the special meeting by holders of U.S. Steel Group Shares (voting as a separate class, with each U.S. Steel Group Share having one vote) and (ii) the holders of a majority of the votes cast at the special meeting by holders of Marathon Group Shares and U.S. Steel Group Shares (voting together as a single class, with each U.S. Steel Group Share having the number of votes, as determined pursuant to the terms of the Restated Certificate, and each Marathon Group Share having one vote) in favor of (A) approval of the United States Steel Corporation 2002 Stock Plan and (B) approval of the United States Steel Incentive Plan. USX shall cause all Marathon Group Shares and U.S. Steel Group Shares for which valid proxies have been submitted and not revoked to be voted at the Stockholders' Meeting in accordance with the instructions on such proxies.

        Section 4.2 Other Securities Matters.

•         (a)   Prior to the Separation Effective Time, USX shall prepare and file with the SEC a registration statement on Form 8-A registering under the Exchange Act the shares of United States Steel Common Stock to be issued in the Separation Merger (the "Form 8-A").

          (b)   Prior to the Separation Effective Time, the parties hereto shall cooperate in preparing and filing with the SEC and causing to be declared effective any registration statements or amendments thereto that are necessary or appropriate in order to reflect the establishment of, or amendments to, any Employee Incentive Plans contemplated by this Agreement or any other Separation Document requiring registration under the Securities Act.

        Section 4.3 Listing.

•         (a)   Prior to the Separation Effective Time, SteelCo shall prepare and submit to the New York Stock Exchange ("NYSE"), the Pacific Stock Exchange ("PSE") and the Chicago Stock Exchange ("CSE") an application for listing on the NYSE, the PSE and the CSE of the shares of United States Steel Common Stock to be issued to holders of U.S. Steel Group Shares in the Separation Merger, and shall use its reasonable efforts to obtain, prior to the Separation Effective Time, approval for the listing of such shares, subject to official notice of issuance.

          (b)   Prior to the Separation Effective Time, USX shall prepare and submit to the NYSE, the PSE and the CSE amendments to USX's listing applications with the NYSE, the PSE and the CSE to provide for the name change of USX to Marathon Oil Corporation and for the delisting of the U.S. Steel Group Shares.

        Section 4.4 Boards of Directors. Prior to the Separation Effective Time, the parties hereto shall take all actions necessary so that, effective as of the Separation Effective Time, the boards of directors of Marathon Oil Corporation and United States Steel Corporation shall include all of the individuals so named in the Proxy Statement.

        Section 4.5 Rights Agreement.

•         (a)   Effective at the Separation Effective Time, United States Steel Corporation shall enter into a Rights Agreement (the "U.S. Steel Rights Agreement"), on substantially the same terms as the Stockholder Rights Plan, pursuant to which one Preferred Stock Purchase Right (as defined in

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• the U.S. Steel Rights Agreement) of United States Steel Corporation (a "U.S. Steel Right") shall be attached to each share of United States Steel Common Stock issued to holders of U.S. Steel Group Shares in the Separation Merger. All references in this Agreement to United States Steel Common Stock shall be deemed to include such a U.S. Steel Right.

          (b)   Prior to the Separation Effective Time, the Stockholder Rights Plan shall be amended to provide that the Steel Rights shall expire at the Separation Effective Time.

        Section 4.6 Preparation of Private Letter Ruling Request. Prior to the Separation Effective Time, USX shall have prepared and submitted to the Internal Revenue Service a request for a private letter ruling, and shall use its reasonable efforts to obtain, prior to the Separation Effective Time, such ruling, in form and substance satisfactory to the Board, that the Separation will qualify as a tax-free transaction within the meaning of Section 355 of the Code.

        Section 4.7 Treatment of USX Corporate Assets and Liabilities. Prior to the Separation Effective Time, each of USX and SteelCo shall use reasonable efforts to take all actions necessary so that (a) all of USX's right, title and interest in and to the USX Corporate Assets listed on Section 4.7(a) of the Disclosure Letter shall be transferred and assigned to SteelCo, and (b) all of USX's Liabilities listed on Section 4.7(b) of the Disclosure Letter shall be assumed by SteelCo, in each case, effective as of the Separation Effective Time.

        Section 4.8 Financings and Value Transfer. Prior to the Separation Effective Time, each of USX and SteelCo shall use reasonable efforts to take all actions necessary to effect (a) the repayment or retirement of certain indebtedness and other obligations of USX; and (b) the incurrence of new indebtedness and other obligations, in each case, in such amounts and on such terms as the parties mutually agree (collectively, the "Financings"); provided that, at the Separation Effective Time, the amount of indebtedness and other obligations for which United States Steel Corporation is responsible immediately following the Separation shall be $900 million less than the net amounts attributed to the U.S. Steel Group immediately prior to the Separation (the "Value Transfer"). The Value Transfer shall be effective at the Separation Effective Time and shall be implemented in accordance with this Section 4.8 and Sections 5.3 and 5.14 hereof.

        Section 4.9 Formation of Merger Sub. USX has organized Merger Sub as a corporation, pursuant to the DGCL, wholly owned by USX. Merger Sub has no assets or Liabilities and shall conduct no business, other than in connection with its organization.

        Section 4.10 Execution of Separation Documents. Prior to the Separation Effective Time, each of USX and SteelCo shall execute and deliver, or cause to be executed and delivered, each of the following documents and any other Separation Document reasonably requested by any party hereto:

•         (a)   A financial matters agreement, substantially in the form of Appendix C hereto (the "Financial Matters Agreement");

          (b)   A tax sharing agreement, substantially in the form of Appendix D hereto (the "Tax Sharing Agreement");

          (c)   A transition services agreement, substantially in the form of Appendix E hereto (the "Transition Services Agreement");

          (d)   A license agreement, substantially in the form of Appendix F hereto (the "License Agreement");

          (e)   An insurance assistance agreement, substantially in the form of Appendix G hereto (the "Insurance Assistance Agreement"); and

          (f)    A sublease relating to the Fairfield Caster in the form of Appendix H hereto (the "Fairfield Caster Sublease").

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        Section 4.11 Other Securities Matters.

•         (a)   QUIPS. In connection with the Separation, each issued and outstanding 6.75% Convertible Quarterly Income Preferred Security of USX Capital Trust I, a subsidiary of USX, will be redeemed for $50.00 in cash, plus accrued and unpaid dividends thereon through the Separation Effective Time.

          (b)   DRIP Plans.

  •         (i)    Effective at the Separation Effective Time, United States Steel Corporation shall adopt a direct stock purchase and dividend reinvestment plan with respect to United States Steel Common Stock (the "Steel DRIP Plan"), substantially on the terms of the USX direct stock purchase and dividend reinvestment plan presently in effect (the "USX DRIP Plan").

            (ii)   Prior to the Separation Effective Time, the USX DRIP Plan shall be amended to provide for USX's name change to Marathon Oil Corporation and to eliminate provisions relating to the U.S. Steel Group Shares. At the Separation Effective Time, all shares of United States Steel Common Stock in the USX DRIP Plan shall be transferred to the Steel DRIP Plan.

        Section 4.12 United States Steel Equity and Incentive Compensation Plans. Prior to the date hereof, the USX board of directors has approved and recommended to SteelCo, as the sole member of SteelCo, that it adopt (i) an equity incentive compensation plan, substantially in the form of Appendix I hereto (the "United States Steel Corporation 2002 Stock Plan"), and (ii) the United States Steel Corporation Senior Executive Officer Annual Incentive Compensation Plan, substantially in the form of Appendix J hereto (the "United States Steel Incentive Plan"), in each case, effective as of the Separation Effective Time.

        Section 4.13 Treatment of Tax-Qualified Pension Assets. USX Corporate Employees and U.S. Steel Group Employees will accrue benefits under the United States Steel Corporation Plan for Non-Union Employee Pension Benefits (Revision of 1998) (the "USS Non-Union Plan") for continuous service performed prior to the date on which they transfer employment to Marathon Oil Corporation or SteelCo. All assets under the USS Non-Union Plan that are attributable to the USX Corporate Employees and the U.S. Steel Group Employees will be retained by the trust under the USS Non-Union Plan. Benefit liabilities with respect to the USX Corporate Employees and the U.S. Steel Group Employees under the USS Non-Union Plan up to the date of transfer will remain liabilities of the USS Non-Union Plan and SteelCo.

ARTICLE V

The Separation

        Section 5.1 The Separation. At the Separation Effective Time, upon the terms and subject to the conditions of this Agreement and in accordance with Section 251 of the DGCL, Merger Sub shall be merged with and into USX. Following the Separation Merger, USX shall continue as the surviving corporation (the "Separation Surviving Corporation") and the separate corporate existence of Merger Sub shall cease in accordance with the DGCL.

        Section 5.2 Separation Effective Time; Closing of the Separation Merger.

•         (a)   Subject to the provisions of this Agreement, the Separation Merger shall be consummated by filing an appropriate certificate of merger (the "Separation Certificate of Merger") with the Secretary of State of the State of Delaware in such form as required by, and executed in accordance with, the relevant provisions of the DGCL as soon as practicable on or before the Separation Closing Date (as defined in Section 5.2(b) hereof). The Separation Merger shall

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• become effective upon such filing or at such time thereafter as is provided in the Separation Certificate of Merger (the "Separation Effective Time").

          (b)   The closing of the Separation Merger (the "Separation Closing") shall take place at the offices of USX, 600 Grant Street, Pittsburgh, Pennsylvania 15219-4776, at 10:00 a.m. (local time), on a date to be specified by the parties (the "Separation Closing Date"), which shall be as soon as practicable after satisfaction or waiver (to the extent and as permitted by this Agreement and Applicable Law) of all of the conditions set forth in Section 6.1 hereof (other than those conditions that by their nature are to be satisfied at the Separation Closing, but subject to the fulfillment or waiver of those conditions), unless the parties agree to another time, date or place in writing.

        Section 5.3 Determination of Cash Settlement Amount.

•         (a)   In connection with the Value Transfer, SteelCo shall pay to USX an amount in cash equal to the Cash Settlement Amount (as hereinafter defined), in accordance with the terms of this Section 5.3, subject to adjustment following the Separation Effective Time pursuant to Section 5.14 hereof. Within thirty (30) days after the date upon which the Separation Effective Time occurs (the "Separation Date"), USX and SteelCo shall jointly prepare and mutually agree upon an estimate of the Cash Settlement Amount (the "Estimated Cash Settlement Amount"), based upon an estimate of the Net Steel Liabilities as of the close of business on the Separation Date ("Estimated Net Steel Liabilities").

          (b)   Within five (5) Business Days following the date upon which USX and SteelCo mutually agree upon the Estimated Cash Settlement Amount pursuant to subsection (a) above, SteelCo shall deliver to USX an amount in cash equal to the Estimated Cash Settlement Amount by wire transfer in immediately available funds, together with interest thereon from the Separation Date through the date such payment is made, at the prime lending rate as reported as of the date of such payment by The Wall Street Journal.

          (c)   If USX and SteelCo are unable to mutually agree upon the Estimated Cash Settlement Amount pursuant to subsection (a) above, SteelCo shall deliver to USX an amount in cash equal to the undisputed portion of the Estimated Cash Settlement Amount by wire transfer in immediately available funds, together with interest thereon from the Separation Date through the date such payment is made, at the prime lending rate as reported as of the date of such payment by The Wall Street Journal.

          (d)   As used herein, "Cash Settlement Amount" shall mean the amount of Net Steel Liabilities less $900 million, and "Net Steel Liabilities" shall mean the net amount of indebtedness and other obligations of USX attributed to the U.S. Steel Group immediately prior to the Separation Effective Time which shall remain an obligation of USX following the Separation Effective Time, and are not otherwise assumed by SteelCo, pursuant to the terms hereof and of the Financial Matters Agreement. The Net Steel Liabilities shall be calculated in good faith in accordance with United States generally accepted accounting principles ("GAAP"), consistently applied, utilizing the same methodology and adjustments as were used in preparing the U.S. Steel Group balance sheet as of June 30, 2001 (the "Steel Balance Sheet").

        Section 5.4 Effects of the Separation Merger. The Separation Merger shall have the effects set forth in Section 259 of the DGCL. Without limiting the generality of the foregoing, and subject thereto, at the Separation Effective Time, all properties, rights, privileges, powers and franchises of Merger Sub shall vest in USX, and all debts, Liabilities and duties of Merger Sub shall become the debts, Liabilities and duties of USX.

        Section 5.5 Organizational Documents. The Restated Certificate and the by-laws of USX, each as in effect immediately prior to the Separation Effective Time, shall be the certificate of incorporation

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and by-laws of the Separation Surviving Corporation, until thereafter amended as provided by the DGCL and such Restated Certificate and by-laws; provided, however, that (a) Article I of such Restated Certificate shall be amended as of the Separation Effective Time to reflect that the name of the Separation Surviving Corporation shall, from and after the Separation Effective Time, be changed to "Marathon Oil Corporation" and (b) Article IV of such Restated Certificate shall be amended and restated as of the Separation Effective Time to provide that the authorized capital stock of Marathon Oil Corporation shall consist of five hundred and seventy-six million (576,000,000) shares of capital stock, of which five hundred and fifty million (550,000,000) shares shall be shares of common stock, par value $1.00 per share, without any specific class designation, and twenty-six million (26,000,000) shares shall be shares of preferred stock, without par value, as set forth in the Amended and Restated Certificate of Incorporation of USX attached as Appendix K hereto.

        Section 5.6 Directors. The directors of USX immediately prior to the Separation Effective Time shall be the directors of the Separation Surviving Corporation from and after the Separation Effective Time and shall hold office until their respective successors are duly elected or appointed and qualified in the manner provided for in the certificate of incorporation and by-laws of the Separation Surviving Corporation, or as otherwise provided by Applicable Law.

        Section 5.7 Officers. The officers of Merger Sub immediately prior to the Separation Effective Time shall be the officers of the Separation Surviving Corporation from and after the Separation Effective Time until the earlier of their resignation or removal or until their successors are duly elected or appointed and qualified in the manner provided for in the certificate of incorporation and by-laws of the Separation Surviving Corporation, or as otherwise provided by Applicable Law.

        Secti