AMENDED AND RESTATED TAX SHARING AGREEMENT

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Exhibit 10.10

AMENDMENT NO. 3
TO
AMENDED AND RESTATED TAX SHARING AGREEMENT

        WHEREAS, Zenith National Insurance Corp. ("Zenith National"), and its subsidiaries Zenith Insurance Company, CalRehab Services, Inc. (formerly ZNAT Rehabilitation Services, Inc.), ZNAT Insurance Company , Zenith Star Insurance Company and Perma-Bilt, a Nevada Corporation (the "Existing Subsidiaries), have previously entered into an Amended and Restated Tax Sharing Agreement ; and

        WHEREAS, effective September 7, 2005, Zenith Star Insurance Company was merged with Zenith Insurance Company and no longer exists as a separate corporate entity; and

        WHEREAS, effective April 17, 2003, the name of Perma-Bilt was changed to Zenith of Nevada, Inc.; and

        WHEREAS, effective May 20, 2004, CalRehab Services, Inc. was