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                                                                 Exhibit 10.5(c)

                                 THIRD AMENDMENT
                                       OF
                          CHICAGO BRIDGE & IRON COMPANY
                      MANAGEMENT DEFINED CONTRIBUTION PLAN
              (AS AMENDED AND RESTATED EFFECTIVE SEPTEMBER 1, 1999)

         Chicago Bridge & Iron Company N.V., a Netherlands company, acting by
and through its sole Managing Director, Chicago Bridge & Iron Company B.V., a
Netherlands company, acting and through its duly authorized and acting Managing
Director, pursuant to Article X of the Chicago Bridge & Iron Company Management
Defined Contribution Plan, as amended and restated effective September 1, 1999
and subsequently amended (the "Plan"), hereby amends the Plan, effective as
provided below, as follows:

                                       I.

         Section 6.2 of the Plan is amended to read as follows:

                  Section 6.2 Part B Participants - Glenn. If Gerald M. Glenn
         consents to the application to him of this Section 6.2 and his Stock
         Account is held in Trust B, the Trustee of Trust B shall distribute and
         release to the Committee and the Committee shall distribute to Mr.
         Glenn (or if applicable, his Beneficiary) all vested amount and all
         vested shares of Stock credited to his Stock Account on the earliest to
         occur of (i) the first business day after his Termination of
         Employment, or (ii) a Change of Control; and prior thereto shall
         distribute to Mr. Glenn (or if applicable, his Beneficiary) vested
         amounts and vested shares of Stock credited to his Stock Account, but
         only during the month of December of each year and only to the extent
         that the distributable amount, when added to all Other Compensation
         paid or accrued by the Company as taxable compensation to such Part B
         Participant for the same tax year of the Company, does not exceed the
         maximum amount thereof that is deductible by the Company after applying
         any applicable limitation under Section 162(m) of the Code.

                  (a)      "Other Compensation" means all other compensation
         (including without limitation dividends payable in respect of
         restricted stock units or shares of restricted stock) previously paid
         or accrued, or which the Company reasonably expects to be paid or
         accrued thereafter under the customary pay practices of the company
         assuming no change such Part B Participant's status or base
         compensation as in effect on the date of the distribution pursuant to
         this Plan, which Other Compensation would be deductible by the Company
         for such Taxable year but for the potential application of Section
         162(m).

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                  (b)      If after receiving a distribution of the Stock
         Account but within the same taxable year of the Company such Part B
         Participant becomes entitled for any reason to receive Other
         Compensation which, when added to such distribution and all Other
         Compensation previously paid or accrued by the Company to such Part B
         Participant for the same taxable year of the company, is in whole or in
         part nondeductible by reason of the application of Section 162(m), such
         Part B Participant shall be deemed to have irrevocably elected to defer
         the receipt of the nondeductible portion of such Other Compensation as
         though such nondeductible portion were an amount distributable from his
         Stock Account.

                                       II.

         The foregoing Amendment shall be effective as of the date of Gerald M.
Glenn's consent thereto.

                                      III.

         Except as provided in this Amendment the Plan shall remain in full
force and effect.

         IN WITNESS WHEREOF, the Company has caused this Amendment to be
executed by its duly authorized officer.

                                   CHICAGO BRIDGE & IRON COMPANY N.V.

                                   By: Chicago Bridge & Iron Company B.V.,
                                       Its sole managing Director

            Date:  May 8, 2003     By: (s) Richard E. Goodrich
                                       -----------------------
                                         its Managing Director

            ATTEST:

            (s) Scott Russell
            -----------------
            Secretary

                                   Consented to by EXECUTIVE

            Date:  May 8, 2003     (s) Gerald M. Glenn
                                   -------------------

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                                    AGREEMENT

         This Agreement dated as of May 8, 2003 is made between Chicago Bridge &
Iron Company, N.V. a Netherlands company (the "Company"), and Gerald M. Glenn, a
Texas resident ("Executive").

                                    RECITALS

         A.       The Company has established for the benefit of certain key
                  employees of the Company and its majority-owned subsidiaries
the Chicago Bridge & Iron Management Defined Contribution Plan, as amended (the
"Plan"). Executive is a participant in the Plan.

         B.       The Company and the Executive have entered into a certain
agreement dated as of September 1, 1999 (the "Plan Agreement"), pursuant to
which among other things the Executive consented to an amendment of the Plan.

         C.       The Company now desired to further amend the Plan and the
Executive desires to consent thereto and the Company and Executive mutually
desire to amend the Plan Agreement.

                                    AGREEMENT

            The Company and Executive agree as follows:

         1.       Executive for himself and his beneficiaries consents to the
Third Amendment to the Plan (the "Plan Amendment") in the form thereof attached
to this Agreement as Exhibit A, and to the application to Executive of Section
6.2 of the Plan as so amended.

         2.       Section 3 of the Plan Agreement is amended by amending clause
(ii) of subsection (a) to read "the first business day after his Termination of
Employment."

         3.       Nothing in this Agreement or in the Plan Amendment shall be
deemed to affect the application of that certain Amendment and Consent Agreement
between the Company and Executive dated as of October 13, 2000, in determining
whether a Change in Control has occurred for purposed of the Plan or the Plan
Agreement.

         IN WITNESS WHEREOF, the Company and Executive have executed this
Agreement as of the date first above written.

                                   CHICAGO BRIDGE & IRON COMPANY N.V.

                                   By: Chicago Bridge & Iron Company B.V.,
                                       Its sole managing Director

            Date:  May 8, 2003     By: (s) Richard E. Goodrich
                                       -----------------------
                                         its Managing Director

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            ATTEST:

            (s) Scott Russell
            -----------------
            Secretary

                                       Consented to by EXECUTIVE

Date:  May 8, 2003                     (s) Gerald M. Glenn
                                       -------------------