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  CERTIFICATION PURSUANT TO CHAPTER 63, TITLE 18 UNITED STATES CODE SS.1350 AS
            ADOPTED BY SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
                  ACCOMPANYING QUARTERLY REPORT ON FORM 10-Q OF
       ARCH CAPITAL GROUP LTD. FOR THE FISCAL QUARTER ENDED JUNE 30, 2002


      I, John D. Vollaro, Executive Vice President and Chief Financial Officer
of Arch Capital Group Ltd. (the "Company"), certify that the accompanying
Quarterly Report on Form 10-Q of the Company for the fiscal quarter ended June
30, 2002 fully complies with the requirements of section 13(a) of the Securities
Exchange Act of 1934 and the information contained in such report fairly
presents, in all material respects, the financial condition and results of
operations of the Company.


                                    Date: August 14, 2002


                                    /s/ JOHN D. VOLLARO
                                    --------------------------------------------
                                    John D. Vollaro
                                    Executive Vice President and Chief
                                    Financial Officer