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Exhibit 10.6

AMENDMENT NO. 5
TO
COST ALLOCATION AGREEMENT

WHEREAS, Zenith National Insurance Corp., Zenith Insurance Company, ZNAT
Insurance Company, CalFarm Insurance Company, CalFarm Insurance Agency, and
Zenith Star Insurance Company, have previously entered into a Cost Allocation
Agreement; and

WHEREAS, Zenith Insurance Company has entered into an agreement to sell 100% of
the common stock of CalFarm Insurance Company to Nationwide Mutual Insurance
Company ("Nationwide"); and;

WHEREAS, CalFarm Insurance Agency is a wholly owned subsidiary of CalFarm
Insurance Company;

IN CONSIDERATION OF THE PREMISES, the parties agree as follows:

1.Effective as of the close of business of the closing date of the sale of
CalFarm Insurance Company to Nationwide, CalFarm Insurance Company and CalFarm
Insurance Agency shall be deleted as parties to the inter-company Cost
Allocation Agreement.

2.In all other respects the Cost Allocation Agreement remains unchanged.

IN WITNESS WHEREOF, each of the undersigned parties has caused this Amendment
No. 5 to be executed on its behalf, this 31st day of March, 1999.

              ZENITH NATIONAL INSURANCE CORP.   ZENITH INSURANCE COMPANY        
      By:   /s/  JOHN J. TICKNER      

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  By:   /s/  JOHN J. TICKNER      

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              ZENITH STAR INSURANCE COMPANY   CALFARM INSURANCE COMPANY        
      By:   /s/  JOHN J. TICKNER      

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  By:   /s/  JOHN J. TICKNER      

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              CALFARM INSURANCE AGENCY   ZNAT INSURANCE COMPANY              
By:   /s/  JOHN J. TICKNER      

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  By:   /s/  JOHN J. TICKNER      

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AMENDMENT NO. 5 TO COST ALLOCATION AGREEMENT