Exhibit 10.17
Fairfax Inc. and Crum & Forster Holding Inc.
Addendum to Tax Sharing Agreement
In order to align the Fairfax, Inc. Tax Allocation Agreement, effective
January 1, 2000, (the “Tax Sharing Agreement” ), with tax planning strategy, and
ensure that the net operating losses of Crum & Forster Holding Inc. (“CFHI”) are
reimbursed by Fairfax, Inc. before their expiration, in the event CFHI
implements the tax planning strategy in which they elect to file a consolidated
tax return with their subsidiaries for financial tax accounting purposes under
the Tax Sharing Agreement, Fairfax Inc. agrees to reimburse CFHI for net
operating losses utilized in consolidation.
IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
by duly authorized officers to be effective January 1, 2005.

           
FAIRFAX, INC
 
      By:   /s/   John Cassil         Name:   John Cassil        Title:   Vice
President       
  Crum & Forster Holding Inc.
 
      By:   /s/   Mary Jane Robertson         Name:   Mary Jane Robertson       
Title:   Sr. Executive Vice President