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                                                                     EXHIBIT 4.1

                                AMENDMENT TO THE
                           FIRST AMENDED AND RESTATED
                W. R. BERKLEY CORPORATION 1992 STOCK OPTION PLAN


         WHEREAS, W. R. Berkley Corporation, a corporation organized and
existing under the laws of the State of Delaware (the "Company"), currently
maintains and sponsors the First Amended and Restated W. R. Berkley Corporation
1992 Stock Option Plan (the "Plan") for the benefit of its eligible employees
and the eligible employees of its affiliates; and

         WHEREAS, Article XVII of the Plan provides that the Board of Directors
of the Company (the "Board") may amend the Plan at any time; and

         WHEREAS, effective March 9, 2000, the Board resolved to amend the Plan
as hereinafter set forth;


         NOW, THEREFORE, pursuant to the authority reserved to the Board, the
Plan is hereby amended as follows, effective March 9, 2000:


         The second paragraph of Article VII shall be deleted and the following
shall be inserted in its place:

               "If the Committee shall so determine, payment for shares of stock
          purchased upon exercise of an option granted hereunder may be made by
          delivery of one or more promissory notes or otherwise on an
          installment basis, with terms and conditions as provided in the
          applicable option agreement; provided, however, that in no event shall
          any such promissory note or installment obligation be due and payable
          later than five years from the date of purchase. The optionee shall
          have full voting rights and shall receive all dividends with respect
          to the shares so purchased. Certificates for shares so purchased
          shall, immediately upon issue, be delivered to the Company, endorsed
          in blank by the optionee or accompanied by a separate stock power so
          endorsed, in pledge as security for the payment of the unpaid balance
          of the purchase price. The certificates issued to represent paid
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          shares shall state thereon the total amount of the consideration to be
          paid therefor and the amount paid thereon."


         IN WITNESS WHEREOF, the undersigned, a duly authorized officer of the
Company, has executed this instrument as of the 9th day of March, 2000, on
behalf of the Board.

                                         By:   /s/ Cornelius T. Finnegan, III
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                                             Name: Cornelius T. Finnegan, III
                                                     Senior Vice President-
                                                        General Counsel