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Exhibit 99(c)

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Annual Report of Folksamerica Holding Company 401(k) Saving and Investment Plan (the "Plan") on Form 11-K for the year ending December 31, 2002 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Steven E. Fass, President and Chief Executive Officer of Folksamerica Holding Company, Inc., certify, pursuant to 18 U.S.C. §1350, as adopted pursuant to §906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

•

The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and,



•

The information contained in the Report fairly presents, in all material respects, the financial condition and changes in net assets of the Plan as of and for the periods presented in the Report.

/s/ Steven E. Fass
President and Chief Executive Officer

Date: June 24, 2003

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Annual Report of Folksamerica Holding Company 401(k) Saving and Investment Plan (the "Plan") on Form 11-K for the year ending December 31, 2002 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Theresa Kress, Vice President, Human Resources of Folksamerica Holding Company, Inc., certify, pursuant to 18 U.S.C. §1350, as adopted pursuant to §906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

•

The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and,



•

The information contained in the Report fairly presents, in all material respects, the financial condition and changes in net assets of the Plan as of and for the periods presented in the Report.

/s/ Theresa Kress
Vice President, Human Resources

Date: June 24, 2003

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CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002