Document:

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                                                                   Exhibit 10.10

                                                  August 8, 2001

Mr. Thomas J. Usher
600 Grant Street
Suite 6100
Pittsburgh, PA 15219-4776

Dear Tom,

In connection with the separation of the businesses of the U.S. Steel Group and
Marathon Group pursuant to the Agreement and Plan of Reorganization approved by
the Board of Directors on July 31, 2001 (Separation) and your agreement to serve
as  Chairman, Chief Executive Officer and President of United States Steel
Corporation (USSC), Chairman of the Board of Directors of Marathon Oil
Corporation (Marathon) and Chairman of the Board of Managers of Marathon Ashland
Petroleum LLC (MAP), I am authorized to extend to you, on behalf of Compensation
Committee of USX Corporation (USX), this Completion and Retention Agreement
(Agreement), effective as of the date stated above.

The terms and conditions of our Agreement are as follows.

1.   If the Separation occurs, you will receive a salary  from USSC of
     $1,100,000 for each of years 2002 through 2004, subject to adjustment by
     the Board of Directors of USSC, or a committee thereof.

2.   Subject to the completion of the Separation, you will receive:

     (a)  a restructuring completion bonus of $6,000,000 payable by Marathon on
          the first business day after the effective time of the Separation; and

     (b)  a retention bonus payable by USSC on the third anniversary of the
          effective time of the Separation.  This retention bonus is capped at
          $3,000,000 and is further subject to the following performance
          measures and limitations authorized in (i) and (ii) below.

          (i)  On the third anniversary of the effective time of the Separation,
               (A) the fair value of the aggregate assets of USSC exceeds its
               total liabilities, (B) the fair saleable value of the aggregate
               assets of USSC exceed its probable liabilities, and (C) USSC is
               able to pay and discharge its debts and other liabilities as they
               become due.  The satisfaction of the foregoing performance
               measures shall be determined solely by the Board of Directors of
               USSC, or the Compensation Committee thereof.

          (ii) In the event the conditions under 2(b)(i) are satisfied, the
               retention bonus of $3,000,000 shall be further subject to the
               performance-related vesting criteria applicable to restricted
               stock under the USSC 2002 Stock Plan (Plan).  Based on a three-
               year rolling
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               average of comparator-company performances and the performance
               criteria established in Appendix A to the Plan, the Compensation
               Committee shall determine the percentage (not to exceed 100%) to
               be applied to the $3,000,000 retention bonus.

3.   Subject to completion of the Separation and in addition to the normal
     director fees paid to non-employee directors, you will receive a $25,000
     annual fee from Marathon for serving as Chairman of the Board of Marathon
     and Chairman of the MAP Board of Managers.

4.   A grant of 90,000 restricted shares of USX-Marathon Group Common Stock with
     (a) 30,000 shares subject to vesting on the first anniversary hereof based
     on the 2001 performance of USX under the USX Stock Plan as determined by
     the Compensation Committee on May 2, 2002, (b) 30,000 shares subject to
     vesting in May 2003 based on the 2002 performance of Marathon under the
     Marathon Stock Plan as determined by the Marathon Compensation Committee in
     May 2003, and (c) 30,000 shares subject to vesting in May 2004 based on the
     2003 performance of Marathon under the Marathon Stock Plan as determined by
     the Marathon Compensation Committee in May 2004.

5.   Subject to the completion of the Separation, a grant of phantom stock
     appreciation rights for 500,000 shares of Marathon common stock.  The
     exercise price of 150,000 shares will be based on the average of the high
     and low market price of USX-Marathon Group Stock Common Stock on the last
     trading day before the effective time of the Separation, and the exercise
     price of 350,000 shares will be based on the average of the high and low
     market price of Marathon common stock on the first trading day after the
     effective time of the Separation.  The effective date of each grant will be
     the same date as the determination of the exercise price.  These stock
     appreciation rights will vest on the effective date of the grant and will
     expire on the earlier of ten years from the effective date of grant, nine
     years following retirement or three years following death while employed.
     These rights will be paid in cash upon exercise.

6.   Subject to completion of the Separation, if you elect to receive your non-
     qualified pension plan as a lump sum distribution, the applicable interest
     rate and mortality table in effect for retirements on December 31, 2001
     will be used to calculate the amount of such pension instead of the
     applicable interest rate and mortality table in effect at the time of your
     retirement, which could be greater or less than such rate.

7.   Other provisions.  The following provisions are further subject to the
     ----------------
     completion of the Separation.

     (a)  In the event of any merger, consolidation or other business
          combination involving USSC which has not been approved by the Board of
          Directors of USSC, all benefits payable hereunder shall immediately
          become due and payable.

     (b)  This Agreement shall be binding upon and inure to the benefit of the
          parties hereto and their respective successors and assigns.  Your
          rights hereunder are not assignable.  We may assign our rights or a
          portion thereof to USSC or to any successor to USSC in a transaction
          approved by the Board of Directors of USSC.

     (c)  Except as otherwise provided herein, in the event of your death prior
          to the satisfaction of any benefit payable hereunder, any such benefit
          that

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          remains unsatisfied at such date shall immediately become due and
          payable, including the vesting of any restricted stock or stock
          appreciation rights.

     (d)  In the event that you voluntarily leave the employment of USSC on or
          before December 31, 2004, the benefits payable under paragraphs 1 and
          3 hereof shall be pro-rated based on the time elapsed.

     (e)  You agree that you will dedicate your full attention and efforts to
          the management and direction of both Marathon and USSC and that you
          will be diligent in acting in the best interests of these
          organizations.

     (f)  We reserve the right to terminate this Agreement for good cause.

Except for your salary set forth in paragraph 1 hereof, it is further understood
that the foregoing benefits are not benefit bearing under any tax-qualified or
non tax-qualified plan of USX, Marathon, USSC or MAP.

Because of your extensive experience and personal qualities, you can make a
unique and valuable contribution to the future of Marathon and USSC.  If the
terms and conditions herein are acceptable, please sign below.

                                        Sincerely,

                                        USX CORPORATION

                                        By: /s/ Seth E. Schofield
                                           -----------------------------
                                             Seth E. Schofield
                                              On Behalf of the
                                              Compensation Committee
                                              Of USX Corporation,
                                              predecessor to Marathon
                                              Oil Corporation

Agreed to and Accepted this 8th day of August, 2001.

/s/ Thomas J. Usher
--------------------------
     Thomas J. Usher

UNITED STATES STEEL LLC, predecessor
to United States Steel Corporation

Agreed to and Acknowledged

By: /s/ E. F. Guna
   -----------------------
Name:  E. F. Guna
     --------------------
Title: Vice President
      -------------------
Date:  August 8, 2001
     --------------------
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                                                                   Exhibit 10.11

                               [USX LETTERHEAD]

Mr. Dan D. Sandman
2173 Hycroft Dr.
Pittsburgh, PA 15241

September 14, 2001

Dear Dan,

In consideration for your agreeing to serve as Vice Chairman and Chief Legal &
Administrative Officer of United States Steel Corporation, United States
Steel LLC and its successors (the "Corporation") agree to provide you with the
additional pension benefits outlined in paragraphs A. and B. of this agreement
("Agreement") upon your retirement if you are employed by the Corporation for a
period of at least five years following the date that USX Corporation separated
into Marathon Oil Corporation and United States Steel Corporation ("Effective
Date"). In the event of your death prior to retirement, the enhanced pension
benefits provided by this Agreement will be payable even if the five-year
service requirement has not been satisfied and will be calculated as if the date
of your retirement was the day immediately prior to the date of your death.

A. Enhanced Pension Benefits
   -------------------------
   The Corporation will provide a pension supplement to you upon your retirement
   from the Corporation (or to your surviving spouse and/or survivor upon your
   death prior to retirement) equal to the excess of (1) minus (2) below:

   (1) the sum of the pension, surviving spouse's benefits, and/or survivor
       benefits which would be provided on your behalf under the United States
       Steel Corporation for Non-Union Employee Pension Benefits (Revision of
       1998) (or its successor) (hereinafter the "Plan") or the USX Corporation
       Non Tax-Qualified Pension Plan (or its successor) (hereinafter the "Non-
       Qualified Plan"), if such benefits were calculated using -

       (a) your actual age at retirement (or death) plus three years, for
           purposes of applying the Plan's early retirement factors,
       (b) your actual continuous service under the Plan for benefit accrual
           purposes at retirement (or death) plus three years, for purposes of
           determining your regular pension under the Final Earnings provisions
           of the Plan and for purposes of applying the Plan's early retirement
           factors,
       (c) the interest rate and mortality table specified by the Plan for
           calculating lump sum distributions as of the date of your retirement
           (or death), except that the lump sum shall be at least equal to the
           amount that would be provided if the lump sum was calculated using
           the applicable interest rate and mortality table for retirements on
           the later of December 31, 2001 or the Effective Date.
       (d) the actuarial factors and assumptions that are in effect under the
           Plan as of the later of December 31, 2001 or the Effective Date,
           using your actual age (and your spouse's and/or survivor's age) at
           retirement (or death).

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          (e)  the Rule-of-70/80 retirement provisions under the Plan even
               though the period of absence requirements have not been
               satisfied, and

          (f)  your actual age, except as specifically provided above, for
               purposes of determining the amount of your benefits under the
               Plan.

     (2)  the sum of the pension, surviving spouse's benefits, and/or survivor
          benefits which are actually payable on your behalf under the Plan or
          the Non-Qualified Plan as of your retirement (or death).

     For purposes of determining the amounts in (1) and (2) above, benefits will
     be based upon the amount of immediate pension payable in the form of a lump
     sum distribution under the terms of the applicable plan. To the extent a
     pension benefit is payable under this Agreement, it will be paid in the
     form of a lump sum distribution by United States Steel Corporation (or its
     successor).

     You may elect, prior to retirement and in writing to the administrator of
     the Corporation's employee benefit plans, to receive such lump sum
     distribution either:

          (i)  in full on February 1 of the year following the year in which you
               retire, or
          (ii) in up to five annual installments with the first annual
               installment payable within 90 days following your date of
               retirement and the succeeding installments payable on the
               applicable anniversaries of the first payment date.

     Interest would accrue and be payable on the balance due at the rate used
     under the Plan to determine the actuarially equivalent lump sum value of
     participants' benefits under the Plan.

B.   Consent Requirements
     --------------------

     For purposes of the USX Corporation Executive Management Supplemental
     Pension Program and the USX Corporation Non Tax-Qualified Pension Program,
     you will be treated as having Company consent to retire even if you have
     not attained age 60 as of the date of your retirement.

Sincerely,
/s/ T. J. Usher
T. J. Usher

                         Agreed to: /s/ Dan D. Sandman       September 14, 2001
                                    ----------------------
                                       Dan D. Sandman

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