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EXHIBIT 99(c)
WASHINGTON MUTUAL, INC.

CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER

        Pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, Kerry K. Killinger, the Chief Executive Officer of Washington Mutual, Inc., does hereby certify that this report on Form 10-Q fully complies with the requirements of Section 13(a) of the Securities Exchange Act of 1934 and that the information contained in this report fairly presents, in all material respects, the financial condition and results of operations of the Company.

By: /s/  KERRY K. KILLINGER Kerry K. Killinger
Chairman, President and
Chief Executive Officer of
Washington Mutual, Inc.

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EXHIBIT 99(c) WASHINGTON MUTUAL, INC.
CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER