Exhibit 10.3

                                                   AMENDMENT TO
                                                 CORE LABORATORIES
                                      SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN


         WHEREAS,  CORE LABORATORIES N.V. and its participating  affiliates (the
"Company") have heretofore adopted the CORE LABORATORIES SUPPLEMENTAL EXECUTIVE
RETIREMENT PLAN (the "Plan") for the benefit of certain employees and
independent directors of the Company; and

         WHEREAS, the Company desires to amend the Plan in certain respects;

         NOW, THEREFORE, the Plan shall be amended as follows, effective as of
February 28, 2003:

        1.   Section 1.1 is amended by adding thereto new paragraphs (17) and
        (18) to read as follows:

        "(17)Actuarial Equivalent or Actuarial Equivalence: A lump sum
             payment with respect to a Participant that, as of the lump sum
             payment date, is actuarially equal in value to the aggregate
             amounts of the Participant's vested accrued benefit expected to be
             received under the annual installment form of payment based upon
             (i) the  Applicable Mortality Table (as defined in section 417(e)
             (3)(A)(ii)(I)  of the  Internal  Revenue Code) and (ii) using an
             interest rate that is 80% of the applicable federal rate
             (determined under section 1274(d) of the Internal Revenue Code and
             the regulations thereunder) compounded annually, for the month in
             which the lump sum is paid.

        (18) Change in Control: Any of the following: (i) a merger of the
             Company with another entity, a consolidation involving the
             Company, or the sale of all or substantially all of the assets
             of the Company to another entity if, in any such case, (A) the
             holders of equity securities of the Company immediately prior
             to such transaction or event do not beneficially own
             immediately after such transaction or event, in substantially
             the same proportions that they owned the equity securities of
             the Company immediately prior to such transaction or event,
             50% or more of the common equity of the resulting entity, (B)
             the holders of equity securities of the Company immediately
             prior to such transaction or event do not beneficially own
             immediately after such transaction or event, in substantially
             the same proportions that they owned the equity securities of
             the Company immediately prior to such transaction or event,
             equity securities of the resulting entity entitled to 50% or
             more of the votes then eligible to be cast in the election of
             directors generally (or comparable governing body) of the
             resulting entity, or (C) the persons who were members of the
             Board immediately prior to such transaction or event shall not




             constitute at least a majority of the board of directors of
             the resulting entity immediately after such transaction or
             event, (ii) shareholder approval of a plan of dissolution or
             liquidation of the Company, (iii) when any person or entity,
             including a "group" as contemplated by Section 13(d)(3) of the
             Securities Exchange Act of 1934, as amended (the "Exchange
             Act"), (other than a trustee or other fiduciary holding
             securities under an employee benefit plan of the Company or
             any affiliate of the Company), acquires or gains ownership or
             control (including, without limitation, power to vote) of more
             than 30% of the combined voting power of the outstanding
             securities of, (A) if the Company has not engaged in a merger
             or consolidation, the Company, or (B) if the Company has
             engaged in a merger or consolidation, the resulting entity, or
             (iv) a change in the composition of the Board, as a result of
             which fewer than a majority of the supervisory directors are
             Incumbent Directors. For purposes of the preceding sentence,
             (1) "resulting entity" in the context of a transaction or
             event that is a merger, consolidation or sale of all or
             substantially all assets shall mean the surviving entity (or
             acquiring entity in the case of an asset sale) unless the
             surviving entity (or acquiring entity in the case of an asset
             sale) is a subsidiary of another entity and the holders of
             common equity of the Company receive capital stock of such
             other entity in such transaction or event, in which event the
             resulting entity shall be such other entity, (2) subsequent to
             the consummation of a merger or consolidation that does not
             constitute a Change in Control, the term "Company" shall refer
             to the resulting entity and the term "Board" shall refer to
             the board of directors (or comparable governing body) of the
             resulting entity, and (3) "Incumbent Directors" shall mean
             directors who either (A) are directors of the Company as of
             February 28, 2003, or (B) are elected, or nominated for
             election, to the Board with the affirmative votes of at least
             two-thirds of the Incumbent Directors at the time of such
             election or nomination, but Incumbent Director shall not
             include an individual whose election or nomination occurs as a
             result of either (A) an actual or threatened election contest
             (as such terms are used in Rule 14a-11 of Regulation 14A
             promulgated under the Exchange Act) or (B) an actual or
             threatened solicitation of proxies or consents by or on behalf
             of a person other than the Board. For purposes of this Section
             1.1(18), all references to the "Company" shall refer solely to
             Core Laboratories N.V. except as expressly provided in clause
             (2) of the preceding sentence."

        2.   Article IV is amended by adding thereto a new Section 4.4 to read
        as follows:

             "4.4 In lieu of the annual installment payments provided by
        Section 4.1, a Participant may irrevocably elect (in such manner as
        proscribed by the Committee) to receive his accrued benefit paid in a
        single lump sum payment on or as soon as administratively feasible
        following a Change in Control. Such lump sum shall be an amount that is
        the Actuarial Equivalent of the installment payments that would
        otherwise be payable to the Participant beginning on his Retirement
        Date (or if such installments have already commenced prior to the


                                      2



        Change in Control, the Actuarial Equivalent of the remaining
        installments due the Participant (or his Designated Beneficiary if he
        has died prior to the Change in Control)). Except as provided in the
        following paragraph, to be effective, the election must be made while
        the Participant is an employee or a director of the Company and at
        least one year prior to both the date of the Participant's 65th
        birthday and the date of the Change in Control.

             If the Participant has not timely made the election provided
        in the preceding paragraph, or is not eligible to make such election as
        provided in the last sentence of such paragraph, then the Participant
        (or, if deceased at the time of the Change in Control, his Designated
        Beneficiary) may irrevocably elect (in such manner as proscribed by the
        Committee) to receive a lump sum payment on or as soon as
        administratively feasible after the Change in Control (or, if the
        election is made following the Change in Control, as soon as
        administratively feasible after the election). The lump sum shall be an
        amount equal to 90% of the Actuarial Equivalence of his then accrued
        benefit (or, if it is already in pay status, the accrued benefit
        remaining to be paid). Upon such lump sum payment, the remaining
        portion of the Participant's accrued benefit automatically shall be
        forfeited."

        3.   Section 9.1 is amended in its entirety to read as follows:

             "9.1 The Board may, in its discretion, amend the Plan, in
        whole or in part, at any time; provided, however, that no amendment
        shall be made that would reduce the accrued benefit of any Participant
        or, without the Participant's written consent, adversely affect any of
        the Participant's rights (vested or contingent) hereunder with respect
        to his accrued benefit, including, without limitation, the timing and
        the form of payment of such benefit and the definition of Actuarial
        Equivalent used to determine the lump sum present value of his accrued
        benefit."

        4.   Section 9.2 is amended in its entirety to read as follows:

             "9.2 The Board may, in its discretion, terminate the Plan in
        whole or in part at any time. In the event the Plan is terminated,
        notwithstanding any other provision of the Plan, the Board, it its
        discretion, may pay each Participant his payable but unpaid vested
        accrued Retirement Benefit (or, in the case of a deceased Participant,
        such Participant's Designated Beneficiary any payable but unpaid Death
        Benefit or Retirement Benefit) either in accordance with Articles IV
        and V, as applicable, or in any other manner the Board deems
        appropriate, including, without limitation, a lump sum payment that is
        the Actuarial Equivalent of such unpaid Retirement Benefit or Death
        Benefit."

        5.  As amended hereby, the Plan is specifically ratified and reaffirmed.

                                       3




        EXECUTED on this 28th day of February, 2003.

                             CORE LABORATORIES N.V.
                             By Core Laboratories International B.V.,
                             its sole managing director


                             By:
                                      ------------------------------------------
                                      Jacobus Schouten
                                      Managing Director of Core Laboratories
                                      International B.V.



                                       4