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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 11-K

        (Mark One)

ý
Annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934


For the fiscal year ended December 31, 2002

OR


Transition report pursuant to Section 15(d) of the Securities Exchange Act of 1934


For the transition period from                     to                    

Commission file number 1-8993

A.
Full title of the plan and the address of the plan, if different from that of the issuer named below:

FOLKSAMERICA HOLDING COMPANY
401(K) SAVINGS AND INVESTMENT PLAN

B.
Name of issuer of the securities held pursuant to the plan and the address of its principal executive office:

WHITE MOUNTAINS INSURANCE GROUP, LTD.
80 South Main Street
Hanover, New Hampshire 03755
(603) 640-2200





Explanatory Note

        This Annual Report on Form 11-K is being filed so that it may be incorporated by reference into a Registration Statement on Form S-8 which White Mountains Insurance Group, Ltd. is filing with respect Common Shares, $1.00 par value per share, of White Mountains Insurance Group, Ltd. issuable under the Plan.


INFORMATION FILED

        The following financial statements and exhibit are filed with, and included in, this Report:



SIGNATURES

        The Plan. Pursuant to the requirements of the Securities Exchange Act of 1934, the trustees (or other persons who administer the employee benefit plan) have duly caused this annual report to be signed on its behalf by the undersigned, thereunto duly authorized.

    Folksamerica Holding Company
401(k) Savings and Investment Plan (the "Plan")

Date: June 27, 2003

 

By:

 

/s/  
STEVEN E. FASS      
Name: Steven E. Fass
Title: President and Chief Executive Officer
          Folksamerica Holding Company Inc.

 

 

By:

 

/s/  
THERESA KRESS      
Name: Theresa Kress
Title: Vice President, Human Resources
          Folksamerica Holding Company Inc.


EXHIBIT INDEX

Exhibit Number            Description




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Explanatory Note
INFORMATION FILED
SIGNATURES
EXHIBIT INDEX