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                                                                    EXHIBIT 10.1


                       ASSUMPTION AND GENERAL AMENDMENT OF
                DIRECTORS' STOCK OPTION AND BENEFIT PROGRAMS AND
             GENERAL AMENDMENT OF EMPLOYEE STOCK OPTION AND BENEFIT
                   PROGRAMS OF WEATHERFORD INTERNATIONAL, INC.

         THIS ASSUMPTION AND GENERAL AMENDMENT INSTRUMENT is hereby made
effective this 26th day of June, 2002 to be effective as hereinafter set forth.

                                   WITNESSETH:

         WHEREAS, pursuant to that certain Agreement and Plan of Merger (the
"Agreement"), dated as of May 8, 2002, among Weatherford International Ltd., a
Bermuda exempted company ("Weatherford Bermuda"), Weatherford International,
Inc., a Delaware corporation ("Weatherford Delaware"), Weatherford U.S.
Holdings, L.L.C., a Delaware limited liability company ("U.S. Holdings") and
Weatherford Merger Inc., a Delaware corporation ("Merger Sub") and a newly
formed, indirect wholly-owned subsidiary of Weatherford Bermuda and a direct
wholly-owned subsidiary of U.S. Holdings, the respective Boards of Directors of
Weatherford Bermuda, Weatherford Delaware, U.S. Holdings and Merger Sub deem it
advisable and in the best interests of their respective stockholders to
reorganize such that Weatherford Bermuda will become the ultimate parent of the
Weatherford group of companies through the merger of Merger Sub with and into
Weatherford Delaware; and

         WHEREAS, subject to the approval of the stockholders of Weatherford
Delaware, the respective Boards of Directors of Weatherford Bermuda, Weatherford
Delaware, U.S. Holdings and Merger Sub (and the stockholders of Weatherford
Bermuda, U.S. Holdings and Merger Sub) have each approved the merger of Merger
Sub with and into Weatherford Delaware, pursuant to which Weatherford Delaware
will be the surviving company in the merger and become a wholly-owned, indirect
subsidiary of Weatherford Bermuda (and a wholly-owned, direct subsidiary of U.S.
Holdings), upon the terms and subject to the conditions set forth in the
Agreement (the "Merger"), and whereby each issued share of common stock, par
value US$1.00 per share, of Weatherford Delaware ("Weatherford Delaware Common
Stock"), including those shares of Weatherford Delaware Common Stock held by
Weatherford Delaware or any direct or indirect wholly-owned subsidiary of
Weatherford Delaware, shall be automatically converted into the right to receive
one common share, par value US$1.00 per share, of Weatherford Bermuda
("Weatherford Bermuda Common Shares"); and

         WHEREAS, Weatherford Delaware currently maintains and sponsors (i) the
Weatherford International Incorporated 1987 Stock Option Plan, as amended and
restated, the Weatherford Enterra, Inc. 1991 Stock Option Plan, as amended and
restated, the Weatherford Enterra, Inc. Amended and Restated Employee Stock
Purchase Plan, the Weatherford Enterra, Inc. Restricted Stock Incentive Plan, as
amended and restated, the Weatherford International, Inc. Executive Deferred
Compensation Stock Ownership Plan and Related Trust Agreement, the Energy
Ventures, Inc. Employee Stock Option Plan, the Weatherford International, Inc.
1998 Employee Stock Option Plan, the Amendment to Stock Option Programs, and
certain other plans and agreements providing for the grant or award to its
officers and employees of options or other rights to purchase or receive
Weatherford Delaware Common Stock (the "Employee Stock Plans") and (ii) the
Weatherford International, Inc. Non-Employee Director Deferred


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Compensation Plan and the Amended and Restated Non-Employee Director Stock
Option Plan, and certain other plans and agreements providing for the grant or
award to its directors of options or other rights to purchase or receive
Weatherford Delaware Common Stock (the "Director Stock Plans"); and

         WHEREAS, the Agreement provides that, following the Merger, Weatherford
Delaware shall continue to maintain and sponsor the Employee Stock Plans and
Weatherford Bermuda shall assume the rights and obligations of Weatherford
Delaware under the Employee Stock Plans and the Director Stock Plans and that
the outstanding options and other awards under the Employee Stock Plans and
Director Stock Plans shall be exercisable or issuable upon the same terms and
conditions as under such plans and the agreements relating thereto immediately
prior to the effective time of the Merger, except that upon the exercise or
issuance of such options or awards, Weatherford Bermuda Common Shares shall be
issuable in lieu of shares of Weatherford Delaware Common Stock so that the
number of Weatherford Bermuda Common Shares issuable upon the exercise or
issuance of such an option or award immediately after the Effective Time and the
option price of each such option or award shall be the number of shares and
option price in effect immediately prior to the Effective Time (as defined in
the Agreement) and all options or awards issued under the Employee Stock Plans
and Director Stock Plans after the Effective Time shall entitle the holder
thereof to purchase Weatherford Bermuda Common Shares in accordance with the
terms of the Employee Stock Plans and Director Stock Plans; and

         WHEREAS, the Agreement further provides that, following the Merger, (i)
Weatherford Delaware shall continue to sponsor and maintain each employee
benefit and program to which Weatherford Delaware is then a party (the "Employee
Benefit Plans"), (ii) Weatherford Bermuda shall assume the rights and
obligations of Weatherford Delaware under each director benefit plan and program
to which Weatherford Delaware is then a party (the "Director Benefit Plans") and
(iii) to the extent any Employee Benefit Plan or Director Benefit Plan provides
for the issuance or purchase of, or otherwise relates to, Weatherford Delaware
Common Stock, after the Effective Time, such plan shall be deemed to provide for
the issuance or purchase of, or otherwise relate to, Weatherford Bermuda Common
Shares; and

         WHEREAS, the consummation of the Merger requires, among other things,
the adoption of this Agreement by the affirmative vote of the holders of a
majority of the outstanding Weatherford Delaware Common Stock entitled to vote
on such adoption (the "Weatherford Delaware Stockholder Approval");

         NOW, THEREFORE, subject to Weatherford Delaware Stockholder Approval,
the Employee Stock Plans, the Director Stock Plans, the Employee Benefit Plans
and the Director Benefit Plans are hereby amended to the extent necessary to
provide as follows:

         1.       Weatherford International Ltd. hereby assumes the rights,
                  duties, obligations of Weatherford International, Inc. under
                  the Employee Stock Plans, and the rights, duties, obligations
                  and sponsorship of Weatherford International, Inc. under the
                  Director Stock Plans and the Director Benefit Plans, and each
                  reference to "Weatherford International, Inc." or "Weatherford
                  Enterra, Inc." (or any predecessor) in any Director Stock Plan
                  and any Director Benefit



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                  Plan is hereby deleted and "Weatherford International Ltd." is
                  hereby substituted in place of such deleted reference.

         2.       Each direct or indirect reference to Weatherford Delaware
                  Common Stock (i.e., common stock, par value U.S. $1.00 per
                  share, of Weatherford International, Inc.) in any Employee
                  Stock Plan, Director Stock Plan, Employee Benefit Plan or
                  Director Benefit Plan is hereby deleted and Weatherford
                  Bermuda Common Shares (i.e., common share, par value US $1.00
                  per share, of Weatherford International Ltd.) is hereby
                  substituted in place of such deleted reference.

         3.       As amended hereby, each affected Employee Stock Plan, Employee
                  Benefit Plan, Director Stock Plan and Director Benefit Plan is
                  specifically ratified and reaffirmed.

         The undersigned, being duly authorized, on behalf of Weatherford
International Ltd. and Weatherford International, Inc., have executed this
Assumption and General Amendment Instrument on the date first set forth above,
to be effective as of the Effective Time of the Merger.


                                              WEATHERFORD INTERNATIONAL LTD.
ATTEST:


By:  /s/ KATHLEEN A. LOPEZ                    By:  /s/ BURT M. MARTIN
   ----------------------------------              -----------------------------
Printed Name:  Kathleen A. Lopez              Printed Name: Burt M. Martin
             ------------------------                      ---------------------
Title:  Executive Assistant                   Title: Director
      -------------------------------               ----------------------------



                                              WEATHERFORD INTERNATIONAL INC.
ATTEST:


By:  /s/ KATHLEEN A. LOPEZ                    By:  /s/ BURT M. MARTIN
   ----------------------------------            -------------------------------
Printed Name:  Kathleen A. Lopez              Printed Name: Burt M. Martin
             ------------------------                      ---------------------
Title:  Executive Assistant                   Title: Senior Vice President
      -------------------------------               ----------------------------


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