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

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant /X/ Filed by a party other than the Registrant / / Check the appropriate box: / / Preliminary Proxy Statement / / CONFIDENTIAL, FOR USE OF THE COMMISSION ONLY (AS PERMITTED BY RULE 14a-6(e)(2)) /X/ Definitive Proxy Statement / / Definitive Additional Materials / / Soliciting Material Pursuant to Section 240.14a-12 White Mountains Insurance Group - -------------------------------------------------------------------------------- (Name of Registrant as Specified In Its Charter) - -------------------------------------------------------------------------------- (Name of Person(s) Filing Proxy Statement, if other than the Registrant) Payment of Filing Fee (Check the appropriate box): /X/ No fee required. / / Fee computed on table below per Exchange Act Rules 14a-6(i)(4) and 0-11. (1) Title of each class of securities to which transaction applies: ------------------------------------------------------------------------ (2) Aggregate number of securities to which transaction applies: ------------------------------------------------------------------------ (3) Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined): ------------------------------------------------------------------------ (4) Proposed maximum aggregate value of transaction: ------------------------------------------------------------------------ (5) Total fee paid: ------------------------------------------------------------------------ / / Fee paid previously with preliminary materials. / / Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing. (1) Amount Previously Paid: ------------------------------------------------------------------------ (2) Form, Schedule or Registration Statement No.: ------------------------------------------------------------------------ (3) Filing Party: ------------------------------------------------------------------------ (4) Date Filed: ------------------------------------------------------------------------ -------------------------

Filed by the Registrantý

Filed by a Party other than the Registranto

Check the appropriate box:
oPreliminary Proxy Statement
oConfidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
ýDefinitive Proxy Statement
oDefinitive Additional Materials
oSoliciting Material Pursuant to § 240.14a-11(c) or § 240.14a-12

White Mountains Insurance Group, Ltd.

(Name of Registrant as Specified In Its Charter)


(Name of Person(s) Filing Proxy Statement if other than the Registrant)
Payment of Filing Fee (Check the appropriate box):
ýNo fee required.
oFee computed on table below per Exchange Act Rules 14a-6(i)(4) and 0-11.
oFee paid previously with preliminary materials.
oCheck box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
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4)Date Filed:



Notice of 2002 2003
Annual General Meeting
of Members (Shareholders) and
Proxy Statement ------------------------- [WHITE MOUNTAINS INSURANCE GROUP LOGO]


GRAPHIC



Table of Contents



Page ----
NOTICE OF 20022003 ANNUAL GENERAL MEETING OF MEMBERS................................................. MEMBERS2
PROXY STATEMENT.................................................................................. STATEMENT3
PROPOSAL 1:ELECTION OF THE COMPANY'S DIRECTORS ................................................. 3
Procedures for Nominating Directors....................................................... 6 Directors7
Voting Securities and Principal Holders Thereof........................................... Thereof7
Compensation of Directors................................................................. 9 Directors10
Compensation of Executive Officers........................................................ 10 Officers11
Compensation Plans........................................................................ 12 Plans15
Reports of the Committees on Executive Compensation....................................... 13 Compensation16
Report of the Audit Committee............................................................. 16 Committee20
Fees Billed by the Company's Independent Auditor for Services Performed in 2001........... 16 200220
Member Return Graph....................................................................... 17 Graph21
Compensation Committee Interlocks and Insider Participation in Compensation Decisions 18 22
Compliance with Section 16(a) of the Exchange Act22
PROPOSAL 2:ELECTION OF DIRECTORS OF FUND AMERICAN REINSURANCE COMPANY, LTD................................... 18 LTD.22
PROPOSAL 3:ELECTION OF DIRECTORS TO ANY NEW NON-UNITED STATES OPERATING SUBSIDIARIES............................. 18 SUBSIDIARIES22
PROPOSAL 4:ISSUANCE OF COMMON SHARES UPON CONVERSION OF CONVERTIBLE PREFERENCE SHARES23
PROPOSAL 5:TECHNICAL AMENDMENTS TO THE LONG-TERM INCENTIVE PLAN25
PROPOSAL 6:APPROVAL OF THE APPOINTMENT OF INDEPENDENT AUDITOR............................... 18 AUDITOR29
OTHER MATTERS................................................................................. 19 MATTERS29
WHITE MOUNTAINS INSURANCE GROUP, LTD. LONG-TERM INCENTIVE PLANAppendix I

        White Mountains Insurance Group, Ltd. (the "Company" and, together with its subsidiaries, "White Mountains") is a Bermuda-domiciled insurance holding company. White Mountains' operations are conducted through its subsidiaries and affiliates in the businesses of property and casualty insurance and reinsurance.

        White Mountains' insurance operations principally include: (i) OneBeacon Insurance Group LLC ("OneBeacon", formerly CGU Corporation), a Boston-based property and casualty insurance holding company and (ii) Folksamerica Holding Company, Inc. ("Folksamerica"), a New York-basedYork City-based property and casualty reinsurance holding company. White Mountains' invested assets are managed by White Mountains Advisors LLC ("WM Advisors"), a wholly-owned registered investment advisor based in Guilford, Connecticut.

The 20022003 Annual General Meeting will be confined to a discussion and Member vote on the proposals set forth in this Proxy Statement and on such other matters properly brought before the meeting. As in past years, management will provide Members and all interested parties with a summary of White Mountains' current operations at an informational meeting to be held at 10:00 a.m. Eastern Time on Thursday, May 23, 200222, 2003 at the Waldorf Astoria Hotel in New York City. Detailed instructions for participating in the informational meeting either in person or via live web cast will be posted at www.whitemountains.com approximately 30 days in advance of the meeting.

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WHITE MOUNTAINS INSURANCE GROUP, LTD.
NOTICE OF 20022003 ANNUAL GENERAL MEETING OF MEMBERS
TO BE HELD MAY 20, 2002 March 22, 200219, 2003

        April 7, 2003

        Notice is hereby given that the 20022003 Annual General Meeting of Members of White Mountains Insurance Group, Ltd. will be held on Monday, May 20, 2002,19, 2003, at 9:12:00 a.m.noon Atlantic Time at the Princess Hotel, Hamilton, Bermuda. At this meeting you will be asked to consider and vote upon the following proposals:

        The Company's audited financial statements for the year ended December 31, 2001,2002, as approved by the Company's Board of Directors, will be presented at this Annual General Meeting.

        Members of record of Common Sharescommon shares on the record date, Friday, March 22, 2002,21, 2003, (i) who are individuals, may attend and vote at the meeting in person or by proxy or (ii) which are corporations or other entities, may have their duly authorised representative attend and vote at the meeting in person or by proxy. A list of all Members entitled to vote at the meeting will be open for public examination during regular business hours beginning April 1, 20022003 at the Company's registered office located at Clarendon House, 2 Church Street, Hamilton HM DX,11, Bermuda.

        All Members are invited to attend this meeting.

Members are invited to complete and sign the accompanying proxy card to be returned to White Mountains Insurance Group, Ltd., c/o EquiServe Trust Company, N.A. Post Office Box 8643, Edison, New Jersey, 08818-8643, in the envelope provided, whether or not they expect to attend the meeting. Members who hold their common shares in a brokerage account, an employee benefit plan or through a nominee may have the added flexibility of voting their shares by telephone or over the internet.

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WHITE MOUNTAINS INSURANCE GROUP, LTD., C/O EQUISERVE TRUST COMPANY, POST OFFICE BOX 8643, EDISON, NEW JERSEY 08818-9052, IN THE ENVELOPE PROVIDED, WHETHER OR NOT THEY EXPECT TO ATTEND THE MEETING. MEMBERS WHO HOLD THEIR COMMON SHARES IN A BROKERAGE ACCOUNT, AN EMPLOYEE BENEFIT PLAN OR THROUGH A NOMINEE WILL LIKELY HAVE THE ADDED FLEXIBILITY OF VOTING THEIR SHARES BY TELEPHONE OR OVER THE INTERNET. 2 WHITE MOUNTAINS INSURANCE GROUP, LTD.

PROXY STATEMENT

        This Proxy Statement is being furnished in connection with the solicitation of proxies on behalf of the Company's Board of Directors (the "Board") for the 20022003 Annual General Meeting of Members (the "2002"2003 Annual Meeting"), to be held on Monday, May 20, 200219, 2003 at the Princess Hotel, Hamilton, Bermuda. The solicitation of proxies will be made primarily by mail, and the Proxy Statement and related proxy materials will be distributed to registered Members on or about April 1, 2002.7, 2003.

        Holders of the Company's common shares ("Members"), par value $1.00 per share ("Common Shares"), as of the close of business on Friday, March 22, 2002,21, 2003, the record date, are entitled to vote at the meeting.

        You can ensure that your Common Shares are properly voted at the meeting by completing, signing, dating and returning the enclosed proxy card in the envelope provided. Members who hold their Common Shares in a brokerage account, an employee benefit plan or through a nominee will likelymay have the added flexibility of voting their Common Shares by telephone or over the internet. A Member has the right to appoint another person (who need not be a Member) to represent the Member at the meeting by completing an alternative form of proxy which can be obtained from the Corporate Secretary or by notifying the Inspectors of Election (see page 19)29). Every Member entitled to vote has the right to do so either in person or by one or more persons authorised by a written proxy executed by such Member and filed with the Corporate Secretary. Any proxy duly executed will continue in full force and effect unless revoked by the person executing it in writing or by the filing of a subsequent proxy.

        Sending in a signed proxy will not affect your right to attend the meeting and vote. If a Member attends the meeting and votes in person, his or her proxy is considered revoked.

PROPOSAL 1

ELECTION OF THE COMPANY'S DIRECTORS

        The Board is divided into three classes (each a "Class"). Each Class serves a three-year term.

        At the 20022003 Annual Meeting, John J. Byrne, Mark J. Byrne, George J. Gillespie, III, John D. GillespieRaymond Barrette, Howard L. Clark, Jr., Robert P. Cochran and Frank A. OlsonArthur Zankel are nominated to be elected to Class IIIII with terms ending in 2005. THE BOARD RECOMMENDS A VOTE2006.The Board recommends a vote FOR PROPOSALProposal 1 WHICH CALLS FOR THE ELECTION OF THE 2002 NOMINEES.which calls for the election of the 2003 nominees.

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        The current Membersmembers of the Board and terms of each Class are set forth below:
- ------------------------------------------------------------ Director Director Age since - ------------------------------------------------------------ Class I - Term Ending in 2004 Patrick M. Byrne 39 1997 Steven E. Fass 56 2000 K. Thomas Kemp 61 1994 Gordon S. Macklin 73 1987 Joseph S. Steinberg 58 2001 - ------------------------------------------------------------ Class II - Term Ending in 2002* John J. ("Jack") Byrne 69 1985 Mark J. Byrne 40 2001 George J. Gillespie, III 71 1986 John D. Gillespie 43 1999 Frank A. Olson 69 1996 - ------------------------------------------------------------ Class III - Term Ending in 2003 Raymond Barrette 51 2000 Howard L. Clark, Jr. 58 1986 Robert P. Cochran 52 1994 Arthur Zankel 70 1992 ============================================================

Director

 Age
 Director since
Class I—Term Ending in 2004    
 Steven E. Fass 57 2000
 K. Thomas Kemp 62 1994
 Gordon S. Macklin 74 1987
 Joseph S. Steinberg 59 2001

Class II—Term Ending in 2005

 

 

 

 
 John J. ("Jack") Byrne 70 1985
 Mark J. Byrne 41 2001
 George J. Gillespie, III 72 1986
 John D. Gillespie 44 1999
 Frank A. Olson 70 1996

Class III—Term Ending in 2003*

 

 

 

 
 Raymond Barrette 52 2000
 Howard L. Clark, Jr. 59 1986
 Robert P. Cochran 53 1994
 Arthur Zankel 71 1992

*
Nominated at the 20022003 Annual Meeting to a term ending in 2005.2006.

        Patrick M. Byrne, a former Class I director, retired from the Board on February 24, 2003.

        The following information with respect to the principal occupation, business experience, recent business activities involving White Mountains and other affiliations of the nominees and directors has been furnished to the Company by the nominees and directors. 3 CLASS

Class I PATRICK M. BYRNE has been a director of the Company since 1997. Mr. Byrne serves as Chairman and CEO of Overstock.com, an internet shopping service. Mr. Byrne formerly served as President and CEO of Fecheimer Bros. Co., a manufacturer of uniforms and accessories, from 1997 to 1999 and President and CEO of Centricut, LLC, a manufacturer of industrial torch consumable parts, from 1994 to 1999. Mr. Byrne's father, Jack Byrne, is Chairman of the Company. STEVEN

Steven E. FASSFass has been a director of the Company since 2000. Mr. Fass has served as President and Chief Executive Officer of Folksamerica and its subsidiaries including Folksamerica Reinsurance Company since 1984. He joined Folksamerica as its Vice President, Treasurer and Chief Financial Officer in 1980. Mr. Fass also serves as Chairman of Fund American Reinsurance Company, Ltd. ("Fund American Re"), Chairman of Esurance and is a director of Olympus Re Holdings, Ltd. other White Mountains subsidiaries.

K. THOMAS KEMP has servedThomas Kemp currently serves as President ofan advisor to the Company since June 2001 and has been a director since 1994. Mr. Kemp previouslycurrently serves as a director and Chief Financial Officer of Montpelier Re Holdings Ltd. ("Montpelier"). Mr. Kemp formerly served as the Company's President from June 2001 to December 2002, as its Deputy Chairman from January 2000 to June 2001 and as the Company'sits President and CEO from 1997 to 2000 and served as Executive Vice President from 1993 to 1997 and its Vice President, Treasurer and Secretary from 1991 to 1993.has been with White Mountains since 1991. Mr. Kemp is also a director of Fund American Reinsurance Company, Ltd., Folksamerica, Main Street America Holdings, Inc. and, Amlin plc. GORDONand other White Mountains subsidiaries.

Gordon S. MACKLIN has served as Deputy Chairman of the Company since June 2001 andMacklin has been a director of the Company since 1987.1987 and has served as a Deputy Chairman of the Company since June 2001. Mr. Macklin has formerly served as Chairman of White River Corporation, an information services company, from 1993 to 1998, as Chairman of Hambrecht and Quist Group, a venture capital and investment banking company, from 1987 until 1992, and as President of the National Association of Securities Dealers, Inc. from 1970 until 1987. He is Chairman of Fund American Reinsurance Company, Ltd., a director of Worldcom, Inc., Martek Biosciences Corporation, MedImmune Inc., Overstock.com and Spacehab, Inc., and is a trustee, director or managing general partner (as the case may be) of 48 of the investment companies in the Franklin Templeton Group of Funds. JOSEPH

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Joseph S. STEINBERGSteinberg has been a director of the Company since June 2001. Mr. Steinberg has served as the President of Leucadia National Corporation ("Leucadia") since 1978. Mr. Steinberg is also a director of Allcity Insurance Company, MK Gold Company, Finova Group, Inc. and Jordan Industries, Inc. In addition, Mr. Steinberg is Chairman of Olympus Re Holdings, Ltd., Olympus Reinsurance Company Ltd. and HomeFed Corporation. CLASS

Class II JOHN

John J. ("JACK"Jack") BYRNE was appointed CEO of the Company in February 2002 andByrne has served as Chairman of the Company since 1985. Mr. Byrne formerly served as CEO of the Company from February 2002 to December 2002, as Chairman of the Board of Managers of OneBeacon from June 2001 to December 2001, as CEO of the Company from January 2000 to June 2001, as President and CEO of the Company from 1990 to 1997 and as CEO from 1985 to 1990. Mr. Byrne is a manager of OneBeacon and also serves as a director of Folksamerica, Overstock.com and as Chairman of Montpelier Re Holdings Ltd. Twoand is a director of Overstock.com and other White Mountains subsidiaries. Mark Byrne, Mr. Byrne's sons, Patrick Byrne and Mark Byrne, areson, is also directorsa director of the Company. MARK

Mark J. BYRNEByrne was appointed a director of the Company in November 2001. He serves as President and Chief Executive Officer ofMr. Byrne manages West End Capital Management Limited ("West End"). Mr Byrne was Chief Executive Officer of General Re Financial Products from March 2000Limited. Prior to February 2002 and, prior to formingfounding West End, Mr. Byrne held a variety of trading and management positions at Salomon Brothers Inc., Pacific Investment Management Company, Lehman Brothers Inc. ("Lehman") and, most recently, Credit Suisse First Boston. He is a director of Markel Corporation. Mr. Byrne's father, Jack Byrne, is Chairman of the Company. GEORGE

George J. GILLESPIE,Gillespie, III has been a director of the Company since 1986. Mr. Gillespie has been a Partner in the law firm of Cravath, Swaine & Moore ("CS&M") since 1963. He is also a director of The Washington Post Company. CS&M has been retained by White Mountains from time to time to perform legal services. See "Certain Relationships and Related Transactions" and "Compensation Committee Interlocks and Insider Participation in Compensation Decisions." Mr. Gillespie's son, John Gillespie, is also a director of the Company. 4 JOHNCompany and is Chairman and President of WM Advisors.

John D. GILLESPIEGillespie has served as a Deputy Chairman of the Company since January 2003 and serves as Chairman and President of WM Advisors. Mr. Gillespie served as Managing Director of OneBeacon sincefrom June 2001 to March 2003 and has been a director of the Company since 1999. He is also the founder and Managing Partner of his own investment firm, Prospector Partners, LLC ("Prospector"), in Hartford, Connecticut.. Prior to forming Prospector, Mr. Gillespie was President of the T. Rowe Price Growth Stock Fund and the New Age Media Fund, Inc. Mr. Gillespie is a manager of OneBeacon and also serves as a director of FolksamericaMontpelier and Montpelier Re Holdings Ltd.other White Mountains subsidiaries. White Mountains owns limited partnership investment interests which are managed by Mr. Gillespie. See "Certain Relationships and Related Transactions." Mr. Gillespie's father, George Gillespie, is also a director of the Company. FRANK

Frank A. OLSONOlson has been a director of the Company since 1996. He serves as Chairman of The Hertz Corporation ("Hertz"). Mr. Olson served as the CEO of Hertz from 1977 to 1999 and has been with that company since 1964. He is also a director of Amerada Hess Corporation and Becton, Dickinson and Company. CLASS

Class III RAYMOND BARRETTE has served as Managing Director

Raymond Barrette was appointed President and Chief Executive OfficerCEO of OneBeacon since June 2001, serving as Chairman of its Board of Managers since December 2001,the Company on January 1, 2003 and has been a director of the Company since 2000. Mr. Barrette formerly served as Presidentwas CEO of the CompanyOneBeacon from 2000 to June 2001 to December 2002 and servedremains its Chairman. Mr. Barrette joined White Mountains Insurance Group in November 1997 as Executive Vice President and Chief Financial Officer of the Company from 1997 to 2000.Officer. He was formerly a consultant with Tillinghast-Towers PerrinPresident from 1994January 2000 to 1996 and was withJune 2001. Prior to joining White Mountains Mr. Barrette had 23 years of experience in the insurance business, mostly at Fireman's Fund Insurance Company from 1973 to 1993. Mr. BarretteFund. He is also Chairman of Folksamerica Reinsurance and serves as a director of Montpelier Re Holdings Ltd. HOWARDand other White Mountains subsidiaries and affiliates.

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Howard L. CLARK,Clark, Jr. has been a director or advisor to the Board since 1986. He is currently Vice Chairman of Lehman and was Chairman and CEO of Shearson Lehman Brothers Inc. from 1990 to 1993. Prior to joining Shearson Lehman Brothers Inc., Mr. Clark was Executive Vice President and Chief Financial Officer of American Express. He is also a director of Lehman Brothers, Maytag Corporation H Power Corp. and Walter Industries, Inc. Lehman provides various services to White Mountains from time to time. See "Certain Relationships and Related Transactions" and "Compensation Committee Interlocks and Insider Participation in Compensation Decisions." ROBERT

Robert P. COCHRANCochran has been a director of the Company since 1994. Mr. Cochran was a founding principal of Financial Security Assurance Holdings Ltd. ("FSA") and has served FSA in various capacities since 1985. He has been President and CEO and a director of FSA since 1990 and became Chairman in 1997. He is also Chairman of Financial Security Assurance Inc. and Financial Security Assurance (U.K.) Ltd. ARTHUR ZANKEL

Arthur Zankel has been a director or advisor to the Boardboard since 1992. He served as a General Partner of First Manhattan Co. from 1965 to 1999 and was Co-Managing Partner of First Manhattan from 1979 to 1997. Mr. Zankel is currently Senior Managing Member of High Rise Capital Management LP.Advisors LLC. See "Certain Relationships and Related Transactions" and "Compensation Committee Interlocks and Insider Participation in Compensation Decisions." Mr. Zankel is also a director of Citigroup, Inc. and AbleCo. COMMITTEES OF THE BOARD OF DIRECTORS

Committees of the Board of Directors

        The Audit Committee, comprised of Messrs. Clark, Olson, Steinberg and Zankel, has general responsibility forperforms the oversightfollowing functions: (1) engaging the independent auditor, subject to Board and surveillanceMember approval, and negotiating the audit fee on behalf of the accounting, reportingBoard; (2) reviewing with the independent auditor the plan, scope and financial control practices of White Mountains. The Audit Committee annually reviews the qualificationsresults of the Independent Auditor, makesaudit and any recommendations to the Board as toindependent auditor may have for improving or changing the audit and control environment; (3) reviewing and pre-approving any non-audit services the independent auditor performs and considering the effect, if any, this may have on their selection and reviewsindependence; (4) reviewing with our internal auditors the plan, feesscope and results of their audit.audits and investigations; (5) discussing with management, the independent auditor and our internal auditors the adequacy of internal accounting controls and discussing with each of them, independently of the other, any recommendations on matters that any of them considers to be of importance; (6) reviewing White Mountains' accounting principles and its financial reporting policies and practices; (7) reviewing, prior to publication, White Mountains' annual and interim financial statements, earnings releases and other financial information prior to their release to the public; and (8) undertaking other duties as assigned by the Board. Mr. Clark is Chairman of the Audit Committee. 5

        The Compensation Committee, comprised of Messrs. PatrickMark Byrne, Cochran, Macklin, Olson, Steinberg and Zankel, oversees White Mountains' share-based compensation and benefit policies and programs, including administration of the White Mountains Insurance Group Long-Term Incentive Plan (the "Incentive Plan") and related non-qualified deferred compensation plans. Mr. Cochran is Chairman of the Compensation Committee.

        The Human Resources Committee, comprised of Messrs. PatrickMark Byrne, Clark, Cochran, George Gillespie, Macklin, Olson, Steinberg and Zankel, sets the annual salaries and bonuses for officers and certain other key employees. Mr. Cochran is Chairman of the Human Resources Committee. The Investment Committee is an advisory committeeintends to appear in person or by proxy at the meeting to nominate the person or persons specified in the notice; (c) a description of all arrangements or understandings between the Qualified Member and each such nominee and any other person or persons (naming such person or persons) pursuant to which the nomination or nominations are to be made by the Qualified Member; (d) such other information regarding each nominee proposed by such Qualified Member as would have been required to be included in a proxy statement filed pursuant to the Boardproxy rules of the United States Securities and is comprisedExchange Commission (the "SEC") had each such nominee been nominated, or intended to be nominated, by the Board; and (e) the consent of Messrs. Barrette, Jack Byrne, John Gillespie, Kemp, Zankel, certain Memberseach such nominee to serve as a director of senior management and investment professionals.the Company if so elected. The Investment Committee formulates the Company's investment policy and oversees all the Company's significant investing activities. John Gillespie is Chairman of the Investment Committee. On June 1, 2001,meeting may refuse to acknowledge the responsibilitiesnomination of any person not made in compliance with the foregoing procedure.

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Meetings of the Investment Committee were delegated to a new Investment Committee established at OneBeacon. MEETINGS OF THE BOARD OF DIRECTORSBoard of Directors

        During 20012002, the following meetings of the Board were held: sixfive meetings of the full Board, one meetingnine meetings of the Audit Committee, two meetings of the Compensation Committee, one meeting of the Compensation Committee and two meetings of the Human Resources Committee and one meeting of the Investment Committee. In 20012002, each director attended more than 75% of all meetings of the Board including its various committees, except Mr. BarretteSteinberg who was unable to attend the meeting of the Investment Committee. During 2001 there were three additionalseven meetings of the Audit Committee, held solely to review the Company's quarterly financial information prior to the release of such information to the public. At such meetings, the Company encourages the participation of all membersmeeting of the AuditCompensation Committee but only requires participation by its Chairman. Mr. Clark attended all such meetings during 2001. and one meeting of the Human Resources Committee.


PROCEDURES FOR NOMINATING DIRECTORS

        Under the Company's Bye-laws, nominations for the election of directors may be made by the Board or by any Member entitled to vote for the election of directors (a "Qualified Member"). A Qualified Member may nominate persons for election as directors only if written notice of such Qualified Member's intent to make such nomination is delivered to the Secretary not later than: (i) with respect to an election to be held at an annual general meeting, 90 days prior to the anniversary date of the immediately preceding annual general meeting or not later than 10 days after notice or public disclosure of the date of the annual general meeting is given or made available to Qualified Members, whichever date is earlier, and (ii) with respect to an election to be held at a special general meeting for the election of directors, the close of business on the seventh day following the date on which notice of such meeting is first given to Qualified Members.

        Each such notice shall set forth: (a) the name and address of the Qualified Member who intends to make the nomination and of the person or persons to be nominated; (b) a representation that the Qualified Member is a holder of record of Common Shares entitled to vote at such meeting and intends to appear in person or by proxy at the meeting to nominate the person or persons specified in the notice; (c) a description of all arrangements or understandings between the Qualified Member and each such nominee and any other person or persons (naming such person or persons) pursuant to which the nomination or nominations are to be made by the Qualified Member; (d) such other information regarding each nominee proposed by such Qualified Member as would have been required to be included in a proxy statement filed pursuant to the proxy rules of the United States Securities and Exchange Commission (the "SEC") had each such nominee been nominated, or intended to be nominated, by the Board; and (e) the consent of each such nominee to serve as a director of the Company if so elected. The chairman of the meeting may refuse to acknowledge the nomination of any person not made in compliance with the foregoing procedure. 6


VOTING SECURITIES AND PRINCIPAL HOLDERS THEREOF VOTING RIGHTS OF MEMBERS

Voting Rights of Members

        As of March 22, 2002,21, 2003, there were 8,284,1818,357,087 Common Shares and 677,966 Convertible Preference Shares outstanding. The Convertible Preference Shares are not entitled to vote at the 2003 Annual Meeting. Members of record of Common Shares shall be entitled to one vote per Common Share, provided that if and so long as the votes conferred by "Controlled Common Shares" (as defined below) of any person constitute ten percent (10%) or more of the votes conferred by the outstanding Common Shares of the Company, each outstanding Common Share comprised in such Controlled Common Shares shall confer only a fraction of a vote that would otherwise be applicable according to the following formula: [(

[(T divided by 10)-1] divided by C

        Where: "T" is the aggregate number of votes conferred by all the outstanding Common Shares; and "C" is the number of votes conferred by the Controlled Common Shares of such person.

        "Controlled Common Shares" in reference to any person means:

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        The limitations set forth above do not apply to any Member which is a "Byrne Entity" (as defined below) for any matter submitted to the vote of Members, except with respect to the election of directors. "Byrne Entity" means any of Mr. Jack Byrne, any foundation or trust established by Messrs. Jack Byrne, Mark Byrne, Patrick Byrne (a former director), and any associate or affiliate of any of them (or any group of which any of them is a part), as defined under Section 13(d) of the United States Securities Exchange Act of 1934, as amended.

        If, as a result of giving effect to the forgoingforegoing provisions or otherwise, the votes conferred by the Controlled Common Shares of any person would otherwise represent 10% or more of the votes conferred by all the outstanding Common Shares, the votes conferred by the Controlled Common Shares of such person shall be reduced in accordance with the foregoing provisions. Such process shall be repeated until the votes conferred by the Controlled Common Shares of each person represent less than 10% of the votes conferred by all Common Shares. 7 PRINCIPAL HOLDERS OF COMMON SHARES


Principal Holders of Common Shares

        To the knowledge of the Company, there was no person or entity beneficially owning more than 5% of the Common Shares outstanding as of March 22, 2002,21, 2003, except as shown below. Common Shares are the only class of the Company's securities that are eligible to vote.
- ----------------------------------------------------------------------------------------------------------------------- Number of Common Shares Percent of Name and address of beneficial owner beneficially owned (a) Class (b) - ----------------------------------------------------------------------------------------------------------------------- Berkshire Hathaway Inc. 1440 Kiewit Plaza, Omaha, NE 68131 1,714,285 17.1% Franklin Mutual Advisers LLC 51 JFK Parkway, Short Hills, NJ 07078 (c) 1,184,246 14.3% Jack Byrne 28 Gates Street, White River Junction, VT 05001 (d) 1,150,101 13.9% - -----------------------------------------------------------------------------------------------------------------------

Name and address of beneficial owner

 Number of
Common Shares
beneficially owned(a)

 Percent of
Class(b)

 
Berkshire Hathaway Inc. 1440 Kiewit Plaza, Omaha, NE 68131 1,724,200 17.1%
Franklin Mutual Advisers LLC 51 JFK Parkway, Short Hills, NJ 07078(c) 1,254,467 15.0%
Jack Byrne 80 South Main Street, Hanover, NH 03755(d) 1,111,818 13.3%

(a)
The Common Shares shown as beneficially owned by Berkshire Hathaway Inc. ("Berkshire") represent Common Shares issuable upon the exercise of warrants to acquire Common Shares. Berkshire cannot vote the Common Shares underlying the warrants until they are exercised. The warrants are currently exercisable.

(b) Represents
Based upon the percentage of total Common Shares outstanding at March 22, 200221, 2003 for all holders shown above except for Berkshire. For Berkshire, this figure represents Berkshire's percentage of all Common Shares outstanding assuming the exercise of its warrants to acquire 1,714,2851,724,200 Common Shares which are currently exercisable. Shares.

(c)
The Common Shares beneficially owned by Franklin Mutual AdvisorsAdvisers LLC ("Franklin") were acquired for investment purposes on behalf of client investment advisory accounts. Excludes convertible preference shares to acquire 677,966 Common Shares purchased by Franklin on October 24, 2002 which are not voting securities of the Company. See Proposal 4.

(d)
Includes 650,000380,909 Common Shares owned directly by the Jack Byrne 2001 GRAT No. 1 and 277,300 Common Shares owned directly by the Jack Byrne 2003 GRAT No. 1 which are deemed to be indirectly beneficially owned by Mr. Byrne. Does not include 25,000 unearned Restricted Common Shares ("Restricted Shares") and 53,86363,133 Common Shares contributed to trusts and charitable foundations for which Mr. Byrne disclaims beneficial ownership, but for which his spouse retains voting power.

8 BENEFICIAL STOCK OWNERSHIP OF DIRECTORS AND EXECUTIVE OFFICERS



Beneficial Stock Ownership of Directors and Executive Officers

        The following table sets forth, as of March 22, 2002,21, 2003, beneficial ownership of Common Shares by each director of the Company, by certain named Executive Officers, and by all Directors and Executive Officers as a group.
- ------------------------------------------------------------------------------------------------------------------------ Number of Common Shares owned ---------------------------------------------- Directors and Executive Officers Beneficially(a)(b) Economically(c) - ------------------------------------------------------------------------------------------------------------------------ Raymond Barrette 29,384 104,942 Jack Byrne (d) 1,150,101 1,205,101 Mark J. Byrne 196,031 196,031 Patrick M. Byrne 236,008 236,008 Howard L. Clark, Jr. 1,000 1,000 Robert P. Cochran 25,000 25,000 Steven E. Fass 5,315 19,015 George J. Gillespie, III 1,000 1,000 John D. Gillespie (e) 101,676 135,676 K. Thomas Kemp 93,141 111,227 Gordon S. Macklin 15,000 17,000 Frank A. Olson 3,000 3,000 James J. Ritchie 2 16,600 Joseph S. Steinberg (f) 0 0 Arthur Zankel 11,600 11,600 All Directors and Executive Officers as a group (18 persons) (g) 1,873,762 2,113,706 ========================================================================================================================

 
 Number of
Common Shares owned

Directors and Executive Officers

 Beneficially (a)(b)
 Economically (c)
Raymond Barrette 28,041 125,721
Jack Byrne(d) 1,111,818 1,159,818
Mark J. Byrne(e) 196,031 196,031
John P. Cavoores 367 21,007
Howard L. Clark, Jr. 1,000 1,000
Robert P. Cochran 25,000 25,000
Steven E. Fass 6,411 27,211
George J. Gillespie, III 1,000 1,000
John D. Gillespie(f) 101,698 148,698
K. Thomas Kemp 93,142 107,211
Gordon S. Macklin 15,000 17,000
Frank A. Olson 3,000 3,000
Joseph S. Steinberg(g) 0 0
Arthur Zankel 11,600 11,600
All Directors and Executive Officers as a group (19 persons) 1,599,350 1,888,139

(a)
The Common Shares beneficially owned by Messrs Jack Byrne, Mark Byrne, Patrick Byrne, John Gillespie, Kemp and all Directors and Executive Officers as a group represent 13.9%13.3%, 2.4%, 2.8%2.3%, 1.2%, 1.1% and 22.6%19.1% of the total Common Shares outstanding at March 22, 2002,21, 2003, respectively. AllNo other Directors andDirector or Executive OfficersOfficer beneficially owned less than 1% or more of the total Common Shares outstanding at that date. Beneficial ownership has been determined in accordance with Rule 13d-3(d)(1) of the Securities Exchange Act of 1934.

(b)
Includes vested and unexercised options ("Options") to acquire 1,4651,365 and 1,8002,700 Common Shares for Messrs. Barrette and Fass, respectively. Excludes unearned Restricted Shares.

(c)
Incremental Common Shares shown as economically owned by Directors and Executive Officers represent unearned performance share awards, unvested Option awards, unearned Restricted Shares and earned phantom shares on compensation deferred.

(d)
Includes 380,909 Common Shares owned directly by the Jack Byrne 2001 GRAT No. 1 and 277,300 Common Shares owned directly by the Jack Byrne 2003 GRAT No. 1 which are deemed to be indirectly beneficially owned by Mr. Byrne. Does not include 53,86363,133 Common Shares contributed to trusts and charitable foundations for which Mr. Byrne disclaims beneficial ownership, but for which his spouse retains voting power.

(e)
The Common Shares shown for Mr. Byrne are held in trust for the benefit of others and he thereby disclaims beneficial ownership of such Common Shares.

(f)
Includes 100,000 Common Shares owned by various funds of Prospector in which Mr. Gillespie is either general manager or investment manager. Mr. Gillespie disclaims beneficial ownership of such Common Shares owned by Prospector except to the extent of his pecuniary interest in such funds. (f)

(g)
Does not include any interest in 375,000 Common Shares (approximately 4.5% of the total Common Shares outstanding)outstanding at March 21, 2003) owned by Leucadia. Mr. Steinberg is the President of Leucadia and, together with certain family members, Mr. Steinberg currently beneficially owns approximately 16.7%15.8% of the common shares of Leucadia. By virtue of his beneficial ownership of Leucadia, Mr. Steinberg may be deemed to be thean indirect beneficial owner of his pro rata share of the Common Shares owned by Leucadia. (g) Includes, in addition to the listed Directors and Executive Officers, Common Shares owned by: (i) John P. Cavoores, OneBeacon's President and Chief Operating Officer who became an Executive Officer in February 2002, (ii) Dennis P. Beaulieu, the Company's Treasurer and Corporate Secretary, and (iii) J. Brian Palmer, the Company's Chief Accounting Officer. Messrs. Beaulieu and Palmer were Executive Officers during 2001.

9



COMPENSATION OF DIRECTORS COMPENSATION OF DIRECTORS

Compensation of Directors

        Messrs. PatrickMark Byrne, Clark, Cochran, George Gillespie, Macklin, Olson, Steinberg and Zankel each received a retainer of $60,000 as a director during 20012002 and fees of $1,000$2,000 for each Board meeting and committee meeting attended through October 2001 and $2,000 per Board meeting and committee meeting thereafter. The annual retainer relates to the twelve month period from May 2001 to May 2002. Mr. Mark Byrne received a prorated retainer of $25,000 which relates to the five month period from December 2001 to May 2002.attended. Messrs. Clark and Cochran also received additional retainers of $5,000 and $10,000 during 20012002 for their roles as Chairman of the Audit Committee and Chairman of the Compensation and Human Resources Committees, respectively. Each of the retainers mentioned above relate to the twelve month period from May 2002 to May 2003. Messrs. Barrette, Jack Byrne, Barrette, Fass, John Gillespie Kemp and MacklinKemp did not receive compensation for their role as a director during 2001. 9 2002.

        During 2002, Mr. Macklin also received $55,125 in compensation for his role as a Deputy Chairman of the Company through March 1, 2002 but no longer receives any further compensation for that role.

10



COMPENSATION OF EXECUTIVE OFFICERS SUMMARY COMPENSATION TABLE

Summary Compensation Table

        The following tables set forth certain information regarding the salary, incentive compensation and benefits paid by White Mountains with respect to 20012002 to its President (its Principal Executive Officer),CEO, its four most highly compensated Executive Officers and twoits former Executive OfficersPresident (collectively, the "Named Executive Officers").

- ----------------------------------------------------------------------------------------------------------------------





Long-Term Compensation ----------------------------------- ------------------------------------



Annual Compensation
Awards
Payouts ----------------------------------- ---------------------- ----------- Other Restricted Annual Share Securities All Other

Name and Compen- Awards Underlying LTIP Compen-
Principal Position

Year
Salary($)
Bonus ($) sation($
Other
Annual
Compensation
($)

Restricted
Share
Awards
($)(a)

Securities
Underlying
Options (#)

LTIP
Payouts ($) sation
($)(b) - ---------------------------------------------------------------------------------------------------------------------- K. THOMAS KEMP

All Other
Compensation
($)(c)

Jack Byrne
Chairman and
former CEO(d)
2002
2001 $269,615
2000
$

107,085
398,077
282,692
$

0
0
350,000
0
0
0
$

0 $1,896,000
8,650,000
0 $5,940,000
0
0
0
$ 63,247

6,510,000
0
0
$

80,169
43,674
9,100

Steven E. Fass
President and CEO
of Folksamerica


2002
2001
2000 182,000 75,000



466,000
466,000
466,000



700,000
0
350,000


0
0
0 129,900 1999 400,000 1,308,809



0
865,000
0


0 2,600,000 269,490 - ---------------------------------------------------------------------------------------------------------------------- JOHN
0
9,000



1,726,440
244,845
498,500



31,062
26,310
30,780

John D. GILLESPIE Gillespie
President of
WM Advisors


2002
2001
2000



400,000
400,000
0



330,000
110,000
0


0
0
0



0
1,384,000
0


0
0
0



0
0
0



66,037
3,219
0

John P. Cavoores
Managing Director
of OneBeacon


2002
2001
2000



400,000
400,000
0



320,000
200,000
0


0
0
0



0
519,000
0 OneBeacon 1999


0
0
0



0
0
0



46,292
33,818
0 - ---------------------------------------------------------------------------------------------------------------------- JACK BYRNE 2001 398,077 0 0 8,650,000 0 0 43,674 Chairman 2000 282,692 350,000 0 0 0 0 9,100 1999 0 0 0 0 0 0 0 - ---------------------------------------------------------------------------------------------------------------------- RAYMOND BARRETTE 2001 398,077 0 0 7,044,500 0 3,960,000 44,766 Chairman

Raymond Barrette
President and CEO of CEO(d)


2002
2001
2000



400,000
398,077
333,654



260,000
0
350,000


0
0
0



0
7,044,500
0


0
0
9,000



6,510,000
3,960,000
0



1,367,840
41,016
15,627 OneBeacon 1999 262,692 1,278,776

K. Thomas Kemp
former President(d)


2002
2001
2000



300,000
269,615
182,000



150,000
0
75,000


0
0 1,105,000 462,291 - ---------------------------------------------------------------------------------------------------------------------- JAMES J. RITCHIE 2001 300,422
0




1,896,000
0 346,000


0
0 40,167 Managing Director and CFO 2000
0



1,302,000
5,940,000
0 0 0 0 0 0 OneBeacon 1999 0 0 0 0 0 0 0 - ---------------------------------------------------------------------------------------------------------------------- DAVID G. STAPLES 2001 165,288 13,200 0 1,348,000 0 1,320,000 9,923 Vice President of 2000 147,308 150,000 0 0 9,000 0 5,169 OneBeacon (c) 1999 135,077 1,081,313 0 0 0 520,000 19,489 - ---------------------------------------------------------------------------------------------------------------------- REID T. CAMPBELL 2001 124,519 15,000 0 1,348,000 0 1,320,000 7,807 Vice President of 2000 108,077 150,000 0 0 9,000 0 6,177 OneBeacon (c) 1999 99,077 129,918 0 0 0 520,000 14,816 - ----------------------------------------------------------------------------------------------------------------------



1,771,656
58,247
129,900

(a)
Represents the value of 2001 Restricted Share awards as of their respective award dates. Restricted Shares vest approximately two years from the date of grant based on continuous service by the employee throughout such period. Holders of Restricted Shares are entitled to receive Common Share dividends and such amounts are included in All Other Compensation above. Restricted Shares awarded in February 2001 (vesting(which were repurchased for $.01 per share in December 2002)2002 as described in note (c) below) to Messrs. Byrne, Fass, Gillespie, Cavoores, Barrette and Kemp Gillespie, Byrne, Barrette, Ritchie, Staples and Campbell were 5,000; 0; 0; 3,750; 0; 1,0000; 3,750 and 1,0005,000 shares, respectively. Restricted Shares awarded in June 2001 (vesting June 2003) to Messrs. Byrne, Fass, Gillespie, Cavoores, Barrette and Kemp Gillespie, Byrne, Barrette, Ritchie, Stapleswere 25,000; 2,500; 4,000; 1,500, 17,000 and Campbell were 1,000; 4,000; 25,000; 17,000; 1,000; 3,000 and 3,0001,000 shares, respectively. The aggregate value as of December 31, 20012002 of all outstandingunvested Restricted Shares awarded during 2001 held by Messrs. Byrne, Fass, Gillespie, Cavoores, Barrette and Kemp totalled $8,075,000; $807,500, $1,292,000; $484,500,$5,491,000 and $323,000, respectively.

(b)
Represents the dollar value of Performance Shares and, in the case of Mr. Fass, cash awards under the Folksamerica Holding Company, Inc. Long-term Incentive Plan earned with respect to 2002. The value of earned Performance Shares which were awarded as of January 1, 2000 and declared

11


(c)
Amounts include, when applicable, 401(k) Savings Plan employer matching contributions (which did not exceed $10,200$11,000 per individual), dividends on Restricted Shares, principal credited to a former non-qualified deferred compensation plan (applicable only for 1999), director fees and retainers paid by companies in which White Mountains is entitled to board representation and imputed income items relating primarily to corporate-provided housing, personal use of White Mountains' aircraft and the value of life insurance provided in excess of $50,000 of coverage. The amounts for 20012002 relating to such imputed income items for Messrs. Byrne, Fass, Gillespie, Cavoores, Barrette and Kemp Gillespie, Byrne, Barrette, Ritchie, Stapleswere $23,169; $20,062; $3,037; $46,292; $90,282 and Campbell were $2,095; $450; $43,674; $30,816; $38,090; $250 and $139,$4,356, respectively. The amounts for 2002, 2001 2000 and 19992000 relating to director fees and retainers of affiliates include $45,952; $119,700$57,000; $0 and $71,650$9,100 for Mr. Kemp, $0; $9,100Byrne, $0, $0 and $0 for Mr. ByrneFass, $57,000; $0 and $0; $9,685 and $22,450$0 for Mr. Barrette. The 1999 amountGillespie, $0, $0 and $0 for Mr. Cavoores, $51,500; $0 and $9,685 for Mr. Barrette and $18,300; $45,952 and $119,700 for Mr. Kemp. During 2002, the Company repurchased from Messrs. Barrette and Kemp 3,750 and 5,000 Restricted Shares, respectively, for $.01 per share and each were granted an amount equivalent to the market value of such Restricted Shares ($1,218,750 for Mr. Barrette and $1,625,000 for Mr. Kemp) in various non-qualified deferred compensation plans of the Company and its subsidiaries. Mr. Kemp's 2002 compensation also includes $42,545 in reimbursements principally associated with a Company-sponsored relocation and a $351,917 phantom stock award resulting from the sale$113,000 paid to him by Montpelier Re Holdings Ltd., an affiliate of the Company's former mortgage operations. (c) As a resultCompany, in connection with his role as its Chief Financial Officer.

(d)
Mr. Kemp served as President of the OneBeacon acquisition, on JuneCompany (its Principal Executive Officer at that time) through February 2002. Mr. Byrne served as CEO of the Company from February 2002 through December 2002. Mr. Barrette was appointed CEO of the Company as of January 1, 2001 Messrs. Staples and Campbell no longer met the definition of an Executive Officer. 10 OPTION GRANTS IN LAST FISCAL YEAR2003.


Option Grants in Last Fiscal Year

        No Options were granted to Named Executive Officers during 2001. AGGREGATED OPTION EXERCISES IN LAST FISCAL YEAR AND FISCAL YEAR-END OPTION VALUES2002.


Aggregated Option Exercises in Last Fiscal Year and Fiscal Year-End Option Values

        The following table summarizes, for the applicable Named Executive Officers, Options exercised during the Company's latest fiscal year, and the number and in-the-money value of Options outstanding as of the end of the fiscal year.
- --------------------------------------------------------------------------------------------------------------------------- As of December 31, 2001 -------------------------------- ------------------------------ Number of Securities Underlying Value of Unexercised In-the- Unexercised Options at Fiscal Money Options at Year ended December 31, 2001 Year-End (#) Fiscal Year-End ($) ------------------------------ -------------------------------- ------------------------------ Common Shares Value Name Acquired Realized ($) Exercisable Unexercisable Exercisable Unexercisable - --------------------------------------------------------------------------------------------------------------------------- K. Thomas Kemp 0 $ 0 0 0 $ 0 $ 0 John D. Gillespie 0 0 0 0 0 0 John J. Byrne 0 0 0 0 0 0 Raymond Barrette 335 78,005 1,465 7,200 336,627 1,654,412 James J. Ritchie 0 0 0 0 0 0 David G. Staples 0 0 1,800 7,200 413,603 1,654,412 Reid T. Campbell 0 0 1,800 7,200 413,603 1,654,412 - ---------------------------------------------------------------------------------------------------------------------------
LONG-TERM INCENTIVE PLANS - AWARDS IN LAST FISCAL YEAR

 
  
  
 As of December 31, 2002
 
 Year ended
December 31, 2002

 Number of Securities
Underlying
Unexercised Options at
Fiscal Year-End (#)

  
  
 
 Value of Unexercised
In-the-Money Options at
Fiscal Year-End ($)

Name

 Common Shares Acquired
 Value Realized ($)
 Exercisable
 Unexercisable
 Exercisable
 Unexercisable
Steven E. Fass 0 $0 2,700 6,300 $533,753 $1,245,423
Raymond Barrette 1,000  198,200 1,365 6,300  336,627  1,245,423

12



Long-Term Incentive Plans—Awards in Last Fiscal Year

        Performance Shares.    The following table summarizes the Incentive Planperformance share awards made to the applicable Named Executive Officers during the latest fiscal year exclusive of awards of Restricted Shares which have been presented inyear.

 
  
  
 Estimated Future Payouts (a)
Name

 Number of
Common Shares (#)

 Performance
period for
payout

 Threshold (#)
 Target (#)
 Maximum (#)
John J. Byrne 5,000 3 yrs. 0 5,000 10,000
Steven E. Fass(b) 5,000 3 yrs. 0 5,000 10,000
John D. Gillespie 15,000 3 yrs. 0 15,000 30,000
John P. Cavoores 10,000 3 yrs. 0 10,000 20,000
Raymond Barrette 15,000 3 yrs. 0 15,000 30,000
K. Thomas Kemp 2,000 3 yrs. 0 2,000 4,000

(a)
Performance shares are issued under the Summary Compensation Table. The Long-Term Incentive awards presented below consisted of performance shares. A performance share derives its value from the market value of a Common Share when earned.
- --------------------------------------------------------------------------------------------------------------------- Performance Estimated Future Payouts (a) Number of period for --------------------------------------- Name Common Shares (#) payout Threshold (#) Target (#) Maximum (#) - --------------------------------------------------------------------------------------------------------------------- K. Thomas Kemp 2,000 3 yrs. 0 2,000 4,000 John D. Gillespie 15,000 3 yrs. 0 15,000 30,000 John J. Byrne 15,000 3 yrs. 0 15,000 30,000 Raymond Barrette 15,000 3 yrs. 0 15,000 30,000 James J. Ritchie 8,600 3 yrs. 0 8,600 17,200 David G. Staples 3,000 3 yrs. 0 3,000 6,000 Reid T. Campbell 2,500 3 yrs. 0 2,500 5,000 - ---------------------------------------------------------------------------------------------------------------------
(a) Performance sharesPlan unless otherwise noted and are payable upon completion of pre-defined business goals and are valued based on the market value of Common Shares at the time awards are earned. Performance shares are paid in cash but can be paid in Common Shares if the Board so determines. With respect to all of the 2001 performance shares awarded to Messrs. Kemp, Staples and Campbell and 50% of the 20012002 performance shares awarded to Messrs. Byrne, Barrette, GillespieFass and Ritchie,Kemp, "Target" performance is the attainment of a corporate annualized return on equity ("ROE") of 12.1%12.0% after tax as measured by the Company's growth in its intrinsic business value. With respect to 50% of the 20012002 performance shares awarded to Messrs. Byrne,Cavoores and Barrette, and Ritchie, "Target" performance is the attainment of a 12% ROE, as described above, and 50% is the attainment of an insurance operations trade ratio of 105%102% (the "Trade Ratio") on OneBeacon's core insurance operations. With respect to 50% of the 20012002 performance shares awarded to Mr. Gillespie, "Target" performance is the attainment of a 12% ROE, as described above, and 50% is the attainment of a return on invested assets of 100150 basis points over the applicable return on the two-yearten-year United States treasury bill.rate or 6.5%. See "Reports of the Compensation Committees on Executive Compensation-Compensation Committee" for additional information concerning the 20012002 awards of performance shares to the Named Executive Officers which includes a discussion of the criteria for "Threshold" and "Maximum" determinations. 11 COMPENSATION PLANS PENSION PLANS. Employees

(b)
Mr. Fass' award was issued under the Folksamerica Holding Company, Inc./White Mountains Performance Share Plan which is similar to the Incentive Plan in all respects except that performance shares under that plan are payable solely in cash.

        Other awards.    During 2002, Mr. Fass was also granted a contingent cash award under the Folksamerica Holding Company, Inc. Long-Term Incentive Plan. The "Target" amount of this award was initially determined as 100% of Mr. Fass' eligible base salary (or $466,000) which is subsequently increased or decreased by Folksamerica's ROE during the performance period. With respect to this award, "Target" performance is the attainment of an 14% ROE, as measured by Folksamerica's pretax return on standard capital. See "Reports of the Compensation Committees on Executive Compensation-Compensation Committee" for additional information concerning this award which includes a discussion of the criteria for "Threshold" and "Maximum" determinations.


Equity Compensation Plan Table

        The following table provides information as of December 31, 2002 with respect to Common Shares that may be issued under White Mountains' existing incentive compensation plans. Performance shares awarded under the Incentive Plan and the Performance Plan are typically paid in cash, though they may be paid in Common Shares at the election of the Compensation Committee. For that reason, these plans are listed in the Equity Compensation Plan Table below. The Folksamerica Holding

13



Company, Inc. Long-Term Incentive Plan and the Folksamerica Holding Company, Inc./White Mountains Performance Share Plan are cash-based plans which do not provide for the issuance of Common Shares and are therefore excluded from this table.

Plan category

 (a)
Number of securities to be issued upon exercise or vesting of outstanding options, warrants and rights

 (b)
Weighted average exercise price of outstanding options, warrants and rights

 (c)
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column (a))

Equity compensation plans approved by security holders—Incentive Plan:      234,000
 Performance shares 190,100 $0  
 Restricted Shares 73,500  0  
 Options 61,965  125.31(1) 
  
 
 
Equity compensation plans not approved by security holders—Performance Plan(2):       
 Performance shares 301,577 $0 198,423
  
 
 

(1)
The outstanding Options were granted in February 2000 at an exercise price equal to the underlying market value of Common Shares on the date of grant. The exercise price escalates on a straight-line basis by 6% per annum over the ten-year life of the Options. The weighted average shown above represents the effective exercise price per Option at December 31, 2002.

(2)
The Performance Plan is a long-term incentive plan of OneBeacon which provides for granting of performance shares to certain of its key employees. The performance goals for full payment of performance shares issued under the Performance Plan are eligiblesimilar to receive retirement benefitsthose of the Incentive Plan. The Performance Plan was not subject to Member approval.

14



COMPENSATION PLANS

        Pension Plans.    Benefit accruals under a qualified defined benefit pension plan sponsored by OneBeacon (the "Pension Plan"). The Pension Plan provides OneBeacon's employees with annual retirement income beginning at age 65 equal to the product of (x) the total number of years of participation in the Pension Plan (but not more than 40 years) and (y) 1.3% of the average annual compensation for the highest consecutive 60 month period in the 120 month period prior to retirement ("Final Average Compensation") plus .45% of such Final Average Compensation in excess of Social Security Covered Compensation as defined by the Internal Revenue Service. The Employee Retirement Income Security Act of 1974, as amended ("ERISA"), and the United States Internal Revenue Code, impose maximum limitations on the annual amount of pension benefits which may be paid under the Pension Plan. As a result, OneBeacon also sponsors a non-qualified supplemental retirement plan (the "Supplemental Pension Plan") which provides additional retirement benefits to highly-paidof OneBeacon were frozen for all participating employees and their beneficiaries. Retirement benefits provided under the Supplemental Pension Plan represent the difference between (a) the benefits which would be payable to such persons under the Pension Plan without taking into consideration the limitations imposed by ERISA and the Internal Revenue Code and (b) the maximum annual benefits to which such persons are entitled under the Pension Plan by reasonas of December 31, 2002. As of such limitations. Remuneration covered by the Pension Plandate, Messrs. Byrne, Gillespie, Cavoores and the Supplemental Pension Plan includes salary and, to a lesser extent annual bonus. Long-term incentive awards under the Incentive Plan are excluded from all pension benefits provided by OneBeacon. Due to the timing of the OneBeacon acquisition, at December 31, 2001, Messrs. Gillespie, Byrne, Barrette Ritchie, Staples and Campbell each had only .6less than 1.6 years of credited service with OneBeacon for purposes of accruing pension benefits, therefore,benefits. As a result, each of their respective accrued pensionretirement benefits were insignificant.

        Benefit accruals under a qualified defined benefit pension plan of Folksamerica, were frozen for all participating employees as of December 31, 2002. As of such date, Mr. Kemp,Fass had 22.6 years of credited service and an average final compensation of $172,000. This resulted in Mr. Fass' annual benefit payable at age 65 being set at $63,160 annually for as long as he lives but in no event for less than 10 years.

        Mr. Fass also participates in the Folksamerica Holding Company, Inc. Deferred Benefit Plan, a non-qualified deferred compensation plan for a select group of employees which was also frozen at December 31, 2002. Folksamerica's credits each participant's account annually with amounts based on the additional value of pension and 401(k) benefits earned that were above IRS limits on qualified plan benefits. As of December 31, 2002, Mr. Fass had an employeeaccount value under the Folksamerica Holding Company, Inc. Deferred Benefit Plan of $1,356,921.

        Employees of the Company isare not eligible to receive pension benefits. DEFERRED COMPENSATION PLANS.

        Deferred Compensation Plans.    The Named Executive Officers are eligible to participate in various unfunded, nonqualified plans for the purpose of deferring current compensation for retirement savings (the "Deferred Compensation Plans"). Pursuant to the Deferred Compensation Plans, participants may defer all or a portion of qualifying remuneration payable by the Company, OneBeacon, WM Advisors or OneBeaconFolksamerica which can be invested in various investment options generally available to the investment community.community including Common Shares. Amounts credited to the deferred compensation accounts of such individuals have been included in the Summary Compensation Table. OTHER COMPENSATION ARRANGEMENTS

Other Compensation Arrangements

        Pursuant to the Incentive Plan, under some circumstances Options may become fully exercisable, Restricted Shares may immediately vest and performance shares may become partially or fully payable. Such circumstances are more fully described in the Incentive Plan. Pursuant to an employment agreement dated December 6, 2000, Mr. Ritchie is entitled to receive his annual base salary of $300,000 should OneBeacon end his employment for any reason prior to December 31, 2002.

        Pursuant to an employment agreement dated January 1, 2001, Mr. John Gillespie is entitled to receive an annual base salary of $400,000, an annual bonus of up to 200% of his base salary, minimum grants of performance shares, participation in employee benefit and fringe benefit plans and an indemnity. Under this agreement, Mr. Gillespie may continue his active involvement with his investment management business, Prospector, so long as Mr. Gillespie devotes the requisite time required to fulfill his responsibilities to OneBeacon.WM Advisors. The agreement specifies procedures pursuant to which Prospector's funds have the ability to invest first in opportunities appropriate for both White Mountains and such funds. Either party can terminate the employment agreement upon 30 days notice and, upon termination, Mr. Gillespie is entitled to accrued compensation and a cash payment equal to a pro rated value of his unearned performance share awards. 12 Pursuant to

        In addition, White Mountains has certain revenue sharing agreements with Mr. John Gillespie has agreedrelating to pay White Mountains a portion of the revenueshis interest in Prospector. See "Certain Relationships and distributions allocable to him in connection with his investment management business, in return for White Mountains agreeing to pay the operational expenses of his investment management companies. During 2001, White Mountains received a net payment of $504,600 from Mr. Gillespie under such revenue sharing agreements. In addition, in September 2001, White Mountains entered into a five-year lease at a market-based rate for a building owned by Mr. GillespieRelated Transactions" below.

Certain Relationships and trusts for the benefit of members of his family. At December 31, 2001, White Mountains had $82 million invested in funds managed by Prospector. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONSRelated Transactions

        Mr. Clark is Vice Chairman of Lehman. Lehman has, for a number of years, provided investment banking services to White Mountains. Lehman was the arranger, the administrative agent and a lender

15



under the $875.0 million credit facility used to acquire OneBeacon.finance the acquisition of OneBeacon which was amended in October 2002.

        Mr. George Gillespie is a partner at CS&M. CS&M has, for many years, provided legal services to White Mountains.

        Mr. John Gillespie indirectly through general and limited partnership interests holds a 44% interest in Dowling & Partners Connecticut Fund III, LP ("Fund III"). OneBeacon Professional Partners, Inc. ("OBPP") and Folksamerica Specialty Underwriting, Inc. ("FSUI") have borrowed approximately $8 million and $7 million, respectively, from Fund III in connection with an incentive program sponsored by the State of Connecticut known as the Connecticut Insurance Reinvestment Act (the "Act"). The loans mature in April 2007 and bear interest at the option of OBPP and FSUI at either (1) the greater of (a) the prime rate minus 1% and (b) the federal funds rate minus 0.50% or (2) the eurodollar rate plus 0.325%. The Act provides for Connecticut income tax credits to be granted for qualifying investments made by approved fund managers. The loans made by Fund III to OBPP and FSUI are qualifying investments and, together, have the potential to generate up to $15 million of tax credits that would be shared equally between Fund III on the one hand and OBPP and FSUI on the other. As a result of his interest in Fund III, Mr. Gillespie could realize up to $3.3 million from the tax credits, although any such amount would be subject to the revenue sharing agreements with White Mountains owns limited partnership investment interests which aredescribed above.

        Pursuant to revenue sharing agreements, Mr. John Gillespie has agreed to pay White Mountains a portion of the revenues and distributions allocable to him in connection with Prospector, in return for White Mountains agreeing to pay Prospector's operational expenses. During 2002, White Mountains received a net payment of $38,070 from Mr. Gillespie under such revenue sharing agreements. At December 31, 2002, White Mountains had $60.1 million invested in funds managed by Prospector.

        In September 2001, White Mountains entered into a five-year lease at a market-based rate for a building partially owned by Mr. John Gillespie. See "Other Compensation Agreements."Gillespie and trusts for the benefit of members of his family (the "Gillespie Trusts"). For 2002, the rental payments attributable to Mr. Gillespie's ownership in the building totalled approximately $13,000 and the rental payments attributable to the Gillespie Trusts' ownership in the building totalled approximately $104,000.

        Mr. Zankel is Senior Managing Member of the General Partner of High Rise Capital Advisors LLC, which is the General Partner of High Rise Partners, L.P. At December 31, 2001,2002, White Mountains had $8.8 million in limited partnership investment interests in High Rise Partners, L.P. and White Mountains also ownsowned $36.6 million in investments that are managed by High Rise Capital Management L.P., of which Mr. Zankel is the senior Managing Member.Advisors LLC.

        White Mountains believes that the above transactions were on terms that were reasonable and competitive and, in the case of Lehman, were obtained through a competitive bid process. White Mountains believes that such transactions did not serve to impair the independence of any of the parties involved. Additional transactions of this nature may be expected to take place in the ordinary course of business in the future.


REPORTS OF THE COMMITTEES ON EXECUTIVE COMPENSATION

        The Human Resources Committee and the Compensation Committee (collectively, the "Committees") are comprised entirely of non-employee directors. The Committees are responsible for developing, administering and monitoring the senior executive compensation policies of the Company, OneBeacon, WM Advisors and OneBeacon.Folksamerica. Salary and bonus compensation for the Named executiveExecutive Officers is established by the Human Resources Committee. Share-based compensation (performancesuch as performance shares, Options and Restricted Shares)Shares is established by the Compensation Committee.

        White Mountains' executive compensation policies are designed with one goal in mind - mind—maximization of Member value over long periods of time. The Committees believe that this goal is best

16



pursued by utilising a pay-for-performance program which serves to attract and retain superior executive talent and provide management with performance-based incentives to maximize Member value. Through this compensation program, the Committees seek to maximize Member value by aligning closely the financial interests of White Mountains' management with those of its Members.

        The Committees believe that the most appropriateprincipal measure of Member value created (or lost) is the Company's ROE as measured by growth in its intrinsic value. In determining intrinsic value, the Committees will consider growth in economic value per share with some attention to growth in tangible book value per share, market value per share and such other relevant values, as the Committees may determine, in reaching a balanced conclusion about performance.share. This proprietary measure is viewed by management and the directors as being a conservative measure of the economicintrinsic value of White Mountains and includes the cost of all projected compensation awards. The Committees believe that, over long periods of time, maximizing the Company's ROE will optimize Member returns. 13

        The Committees believe that the performance-based compensation for key employees should be payable in full only if the Company achieves truly superior returns for its Members. Therefore, the target of many of White Mountains' performance-based compensation programs are directly linked to achievement of an annualized ROE at least equal to the market yield available from a ten- yearten-year United States Treasury note plus 700 basis points, or currently 12%.points. The Committees believe that this return is a challenging target for the Company in its current form.

        Compensation of White Mountains' management team, including the Named Executive Officers, consists primarily of three components: base salary, annual bonus and long-term incentive awards. HUMAN RESOURCES COMMITTEE BASE SALARY.

Human Resources Committee

        Base Salary.    Base salary for each Named Executive Officer is established annually, on or about March 1. When establishing base salaries of the Named Executive Officers, the Human Resources Committee considers numerous factors including each Named Executive Officer's qualifications, corporate responsibilities, performance since their last salary adjustment and, except for the CEO, the recommendations of the CEO. ANNUAL BONUS.

        Annual Bonus.    For 20012002, the target annual bonus pool for all the Named Executive Officers, except Mr. Fass, was equal to 50% of eligible base salary at a 12.1%salary. Mr. Fass's target annual ROE with no bonus pool resulting from a ROEfor 2002 was equal to 75% of 5.1% or less.his eligible base salary. When establishing the aggregate size of the annual bonus pool, the Human Resources Committee considers numerous factors including performance versus the objectives set forth in the Company's Annual Business Plan,Plans of the Company, OneBeacon, WM Advisors and Folksamerica, in particular the Company'stheir respective financial performance for the latest fiscal year as measured by ROE or otherwise, and the recommendations of the CEOCEO.

        After establishing the aggregate size of the annual bonus pool, the Human Resources Committee then considers the distribution of the bonus pool among the key employees. Each participant's allocation of the pool is determined after considering numerous factors including individual achievements as compared to objectives includedcontained in the Annual Business Plan,Plans, the contribution of such achievements to the Company's overall financial performance and the recommendations of the CEO.

        The Human Resources Committee determined that the financial results of the Company (the basis for Mr. Kemp's bonus) and OneBeacon (the basis for Messrs. Cavoores and Barrette's bonus) warranted a bonus pool of 130% of target or 65% of eligible base salary. The principal factor considered by the Committee in making this determination was the Company's 2002 ROE performance which was determined to be 15.6%, as measured by its change in intrinsic value per Common Share, versus a 12% target and OneBeacon's 2002 core trade ratio of 98% versus a target of 102%.

        The Human Resources Committee determined that the financial results of Folksamerica (the basis for Mr. Fass' bonus) warranted a bonus pool of 200% of target or 150% of his eligible base salary. The principal factor considered by the Human Resources Committee in making this determination was

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Folksamerica's 2002 ROE performance which was determined to be 23%, as measured by Folksamerica's pretax return on standard capital, versus a target of 14%.

        The Human Resources Committee determined that the financial results of WM Advisors (the basis for one-half of Mr. Gillespie's bonus) warranted a bonus pool of 200% of target. The principal factor considered by the Human Resources Committee in making this determination was WM Advisors' 2002 total investment return performance which was determined to be 11.4% which was viewed by the Committee as being an excellent result in light of current market conditions. The other half of Mr. Gillespie's bonus is dependent upon the financial results of the Company which, as stated above, was determined to warrant a bonus pool of 130% of target. Based on the average of these two measures, Mr. Gillespie's bonus pool was determined to be 165% of target or 82.5% of his eligible base salary.

        Historically, the CEO typically receives an annual bonus equal to the average bonus percentage received by all officers eligible to participate in the bonus pool. For 2001 the Human Resources Committee determined that the financial results of the Company2002, Mr. Byrne's annual compensation was fixed at $100,000 and as such he did not warrantreceive a bonus pool. The principal factor considered by the Human Resourcesbonus.

Robert P. Cochran, Chairman
Mark J. Byrne
Howard L. Clark, Jr.
George J. Gillespie, III
Gordon S. Macklin
Frank A. Olson
Joseph S. Steinberg
Arthur Zankel

Compensation Committee in making this determination was the Company's 2001 ROE performance which was determined to be below the threshold of 5.1%, as measured by its change in economic value per Common Share, versus a 12.1% target ROE. In light of the completion of the OneBeacon transaction and favorable investment results attained during 2001, the Human Resources Committee created a modest special purpose bonus pool for a select group of employees pursuant to which Messrs. John Gillespie, Staples and Campbell received $110,000, $13,200 and $15,000, respectively. No other Named Executive Officers received a bonus for 2001. ROBERT P. COCHRAN, CHAIRMAN PATRICK M. BYRNE HOWARD L. CLARK, JR. GEORGE J. GILLESPIE, III FRANK A. OLSON JOSEPH S. STEINBERG ARTHUR ZANKEL COMPENSATION COMMITTEE LONG-TERM INCENTIVE AWARDS.

        Long-Term Incentive Awards.    The Incentive Plan provides for granting various types of share-based incentive awards including Restricted Shares, Options and performance shares to the Named Executive Officers and certain other key employees of the Company and its subsidiaries.

        Over the past several years, the Company has consistentlyprincipally used performance shares in its long-term compensation plans. Performance shares are payable only upon completion of pre-defined business goals and are valued based on the market value of Common Shares at the time awards are earned. 14 For 2001,Performance shares awarded under the Compensation Committee determined that awards of RestrictedIncentive Plan are paid in cash but can be paid in Common Shares would be an effective supplement to performance share grants and would provide an effective means of retention inif the form of long-term incentive compensation to certain key employees.Board so determines.

        The Compensation Committee believes that awards of performance shares are an attractive method of providing incentives for management to strive to maximize Member value over the long term. This belief is predicated on the following factors: (i) such awards are earned over multi-year periods; (ii) such awards are generally made in the form of Common Shares, or derivatives thereof, which helps to align the interests of management with those of the Company's Members; and (iii) performance shares are contingent upon the achievement of a 12.1%specified ROE, or such other measures as may be selected in advance by the Compensation Committee, over the applicable performance period which further aligns the interests of management and the Company's Members.

        In 20012002, Messrs. Kemp,Byrne, Fass, Gillespie, Byrne,Cavoores, Barrette Ritchie, Staples and CampbellKemp were granted 2,000;5,000; 5,000; 15,000; 15,000; 15,000; 8,600; 3,00010,000; 15,000 and 2,5002,000 performance shares, respectively, by the Compensation Committee. The performance period for such awards began on January 1, 20012002 and will continue through December 31, 2003.2004.

        With respect to the 20012002 performance shares awarded to Messrs. Kemp, StaplesByrne, Fass and Campbell,Kemp, performance is the attainment of a ROE of 12.1%12% after tax which would result in such performance shares being fully earned ("Target"). At a ROE of 5.1%5% or less, no such performance shares would be

18



earned ("Threshold") and at a ROE at or above 23%, 200% of such performance shares would be earned ("Maximum").

        With respect to 50% of the 20012002 performance shares awarded to Messrs. Byrne,Cavoores and Barrette, and Ritchie, performance is the attainment of a ROE of 12.1%12% after tax ROE as defined above.previously described. With respect to the remaining 50% of the 20012002 performance shares awarded to these individuals,Messrs. Cavoores and Barrette, "Target" performance is the attainment of a OneBeacon core insurance operations Trade Ratio of 105%.102% on OneBeacon's Trade Ratio is similar to ancore insurance company's combined ratio but has been modified to divide general operating expenses by earned premiums rather than written premiums. With respect to the Trade Ratio aspect of the attainment goals, atoperations. At a Trade Ratio of 107%106% or more, no such performance shares would be earned ("Threshold") and at a Trade Ratio of 101%96% or less, 200% of such performance shares would be earned ("Maximum").

        With respect to 50% of the 20012002 performance shares awarded to Mr. Gillespie, "Target" performance is the attainment of a ROE of 12.1%12% after tax ROE as defined above.previously described. With respect to the remaining 50% of the 20012002 performance shares awarded to Mr. Gillespie, "Target" performance is the attainment of a return on invested assets of 100150 basis points over the applicable return on the applicable two-yearten-year United States treasury bill. With respect to the investmentrate or 6.5%. At a return aspecton invested assets of the attainment goals, at an investment return equal to5% or less, than the two-year treasury, no such performance shares would be earned ("Threshold") and at an investmenta return equal toon invested assets of 8% or greater than 200 basis points over the two-year treasury,more, 200% of such performance shares would be earned ("Maximum").

        In 20012002, Mr. Fass was granted a contingent cash award under the Named Executive Officers received Restricted SharesFolksamerica Holding Company, Inc. Long-Term Incentive Plan. The "Target" amount of this award was initially determined as 100% of Mr. Fass' eligible base salary (or $466,000) which vest approximately two years fromis subsequently increased or decreased by Folksamerica's ROE during the dateperformance period. With respect this to award, "Target" performance is the attainment of grant basedan 14% ROE, as measured by Folksamerica's pretax return on continuous service throughout such period. Restricted Shares awarded in February 2001 (vesting December 2002) tostandard capital. At a ROE of 7% or less, the award would not be earned ("Threshold") and at a ROE at or above 21%, 200% of the award would be earned ("Maximum").

        Messrs. Kemp,Byrne, Fass, Gillespie, Byrne,Cavoores, Barrette Ritchie, Staples and Campbell were 5,000; 0; 0; 3,750; 0; 1,000 and 1,000 shares, respectively. Restricted Shares awarded in June 2001 (vesting June 2003) to Messrs. Kemp Gillespie, Byrne, Barrette, Ritchie, Staples and Campbell were 1,000; 4,000; 25,000; 17,000; 1,000; 3,000 and 3,000 shares, respectively. Messrs. Kemp, Gillespie, Byrne, Barrette, Ritchie, Staples and Campbell had, pursuant to a 19992000 grant, 9,000; 0; 0; 6,000; 0;10,000, 2,000, 0, 0, 10,000 and 2,000 performance shares eligible for payout, respectively, subject to the attainment of a 13% target ROE. At an ROE of 25% or greater, 200% of such performance shares would be earned. During the 19992000 to 20012002 performance period, the Company attained aan ROE of 28.2%27.8% calculated in accordance with the Incentive Plan. In light of the excellent ROE attained during the performance period, the Compensation Committee determined that 200% of such performance shares were fully earned on February 27, 2002.24, 2003. The dollar value of such performance shares earned are included in the Summary Compensation Table. ROBERT

        Mr. Fass also had, pursuant to a 2000 grant, a contingent cash award under the Folksamerica Holding Company, Inc. Long-Term Incentive Plan. The "Target" amount of this award was initially determined as 100% of Mr. Fass' eligible base salary which is subsequently increased or decreased by Folksamerica's ROE during the performance period. With respect this to award, "Target" performance is the attainment of a 14.7% ROE, as measured by Folksamerica's pretax return on standard capital. At a ROE of 7.35% or less, the award would not be earned. During the 2000-2002 performance cycle, Folksamerica attained an ROE of 12.1%, as calculated in accordance with the Folksamerica Long-Term Incentive Plan, and as such the Compensation Committee determined that 65% of Mr. Fass' award, or $424,440, was earned on February 24, 2003. This amount is included in the Summary Compensation Table.

        During 2002, the Company repurchased from Messrs. Barrette and Kemp 3,750 and 5,000 Restricted Shares, respectively, for $.01 per share and each were granted an amount equivalent to the market value of such Restricted Shares in various non-qualified deferred compensation plans of the

19



Company and its subsidiaries. The dollar value of the deferred compensation grant to Messrs. Barrette and Kemp is included in the Summary Compensation Table.

Robert P. COCHRAN, CHAIRMAN PATRICK M. BYRNE FRANKCochran, Chairman
Mark J. Byrne
Gordon S. Macklin
Frank A. OLSON JOSEPHOlson
Joseph S. STEINBERG ARTHUR ZANKEL 15 Steinberg
Arthur Zankel


REPORT OF THE AUDIT COMMITTEE

        In connection with the audit of the Company's financial statements for the year ended December 31, 2001,2002, the Audit Committee has: (1) reviewed and discussed the audited financial statements with management; (2) reviewed and discussed the disclosures contained within the Annual Report on Form 10-K; (3) reviewed and discussed with the Independent Auditor the matters required by Statement of Auditing Standards No. 61; and (3)(4) reviewed and discussed with the Independent Auditor the matters required by Independence Standards Board Statement No. 1. Based on these reviews and discussions, the Audit Committee has determined itsthat the non-audit fees billed by the Independent Auditor to be independent and havefor services performed in 2002 (as shown below) are compatible with maintaining their independence. Further, the Audit Committee has recommended to the Board that the audited financial statements be included in the Annual Report on Form 10-K for filing with the SEC and for presentation to the Members at the 20022003 Annual Meeting.

        The Audit Committee has established a Charter which outlines its primary duties and responsibilities. The Audit Committee Charter, which has been approved by the Board, is reviewed at least annually and is updated as necessary. The Audit Committee Charter was furnished to the Company's Members in its 2001 Proxy Statement. HOWARD

Howard L. CLARK JR.Clark Jr., CHAIRMAN FRANKChairman
Frank A. OLSON JOSEPHOlson
Joseph S. STEINBERG ARTHUR ZANKEL Steinberg
Arthur Zankel


FEES BILLED BY THE COMPANY'S
INDEPENDENT AUDITOR FOR SERVICES PERFORMED IN 2001 AUDIT FEES.2002

        Audit Fees    Aggregate fees billed for the 20012002 audit of the Company's consolidated financial statements including quarterly reviews totalled $1,637,900. FINANCIAL INFORMATION SYSTEMS DESIGN AND IMPLEMENTATION FEES.$1,952,300.

        Financial Information Systems Design and Implementation Fees    No such services were performed during 2001. ALL OTHER FEES.2002.

        All Other Fees    Aggregate fees billed for all other services performed in 2001 totalled $4,026,800.2002 totaled $4,565,700. These fees related primarily to: (i)i) tax compliance and consulting services for existing companies and consulting and tax structuring services relatingrelated to acquisition activities, (ii) information technology feasibility studies and (iii)ii) audit services related to capital raising activities. 16 activities and statutory reporting requirements and iii) non-financial information systems technology consulting. Of these fees, $1,658,400 related to services provided by PwC Consulting prior to the sale of this division to IBM on October 1, 2002. The services provided by PwC Consulting related to various non-financial information systems technology consulting projects.

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MEMBER RETURN GRAPH

        The following graph shows the five-year cumulative total return for a Member who invested $100 in Common Shares (NYSE symbol "WTM") as of the close of business on December 31, 1996,January 1, 1998, assuming re-investment of dividends. Cumulative returns for the five-year period ended December 31, 20012002 are also shown for the Standard & Poor's 500 Stocks (Property & Casualty) Capitalization Weighted Index ("S&P P&C") and the Standard & Poor's 500 Stocks Capitalization Weighted Index ("S&P 500") for comparison.

        As stated herein, White Mountains' various compensation plans are based on its growth in its economicintrinsic value which is believed to be a conservative proxy for its intrinsic business value. The Company's long-term goal is to maximize its intrinsic business value per Common Share which will, in turn, affect its market value per Common Share. [CHART OF FIVE-YEAR CUMULATIVE TOTAL RETURN]
1997 1998 1999 2000 2001 WTM $127.3 $149.1 $129.8 $346.1 $378.7 S&P P&C 145.5 135.4 100.9 157.1 144.5 S&P 500 133.4 171.5 207.6 188.7 166.2
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GRAPHIC

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COMPENSATION COMMITTEE INTERLOCKS AND
INSIDER PARTICIPATION IN COMPENSATION DECISIONS

        The Company notes certain relationships and transactions pertaining to Messrs. Clark, George Gillespie and Zankel who are Members of the Compensation Committee and/or the Human Resources Committee. See "Certain Relationships and Related Transactions." CERTAIN FILINGS UNDER


COMPLIANCE WITH SECTION 1616(a) OF THE EXCHANGE ACT

        Pursuant to SEC rules relating to the reporting of changes in beneficial ownership of Common Shares, the Executive Officers, Directors and greater than 10% Members are believed to have filed all reports required under Section 16 on a timely basis during 2001. 2002. Mr. Barrette, however, filed an amended Form 5 on March 27, 2003 relating to December 2000 reporting a gift of 385 Common Shares in December 2000.


PROPOSAL 2

ELECTION OF DIRECTORS OF FUND AMERICAN REINSURANCE COMPANY, LTD. ("FUND AMERICAN RE")RE

        Bye-law 77 of the Company provides that the boards of directors of any wholly-owned subsidiary of the Company incorporated under the laws of Bermuda, such as Fund American Re, or any other company designated by the Board, be elected by the Company's Members.

        Proposal 2 calls for the election of Messrs. Kemp,Barrette, Fass, Anders Henriksson (President of Fund American Re) and Ms. Sheila E. Nicoll (President and Chief Executive Officer of Olympus Re Holdings, Ltd,Ltd., a reinsurance company organised under the laws of Bermuda) to the board of directors of Fund American Re. The proposal also calls for the election of Ms. Elinor M. Lucas (an associate of Conyers, Dill & Pearman, the Company's Bermuda counsel) as an alternativealternate to any one or more of the directors of Fund American Re.

        Messrs. Kemp,Barrette, Fass and Henriksson and Ms. Lucas will not receive any compensation for their services as a director of Fund American Re. Ms. Nicoll is expected to receive an annual director retainer of $5,000. Biographical information relating to Messrs. KempBarrette and Fass is presented under Proposal 1 "Election of the Company's Directors." THE BOARD RECOMMENDS A VOTE

The Board recommends a vote FOR PROPOSALProposal 2 WHICH CALLS FOR THE ELECTION OF THE DIRECTORS OF FUND AMERICAN RE. which calls for the election of the directors of Fund American Re.


PROPOSAL 3

ELECTION OF DIRECTORS TO ANY NEW NON- UNITEDNON-UNITED STATES OPERATING SUBSIDIARIES

        Bye-law 77 of the Company provides that the boards of directors of any wholly-owned subsidiary of the Company which is incorporated under the laws of Bermuda, or any other company designated by the Board, be elected by the Company's Members.

        Proposal 3 calls for the election of Messrs. KempBarrette and Fass to any wholly-owned, non-United Statesnon-U.S. operating subsidiary that may be formed by the Company in the future. Messrs. KempBarrette and Fass will not receive any compensation for their services as a director of any newly-formed, non-United Statesnon-U.S. company. Biographical information relating to Messrs. KempBarrette and Fass is presented under Proposal 1 "Election of the Company's Directors."

The Board recommends a vote FOR Proposal 3 which calls for the election of Messrs. Barrette and Fass to any new non-United States operating subsidiaries.

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PROPOSAL 4

ISSUANCE OF COMMON SHARES UPON CONVERSION OF CONVERTIBLE PREFERENCE SHARES

Background

        On October 24, 2002, White Mountains sold $200 million in convertible preference shares (the "Convertible Preference Shares") in a private transaction to Franklin, an existing Member (see page 8). The Convertible Preference Shares are to be repurchased and cancelled by the Company in consideration of 677,966 Common Shares upon approval of this proposal.

        White Mountains used the proceeds from the sale of Convertible Preference Shares to partially repay, on November 29, 2002, a $260 million Seller Note (the "Seller Note") that was issued in connection with White Mountains' 2001 acquisition of OneBeacon. Under Bermuda law and the Company's Bye-laws, the issuance of the Convertible Preference Shares to repay the Seller Note did not require Member approval.

        In contemplation of the repayment of the Seller Note, it was White Mountains' desire to issue, and Franklin's preference to receive Common Shares as part of the financing activities. However, the New York Stock Exchange, Inc. (the "Exchange"), which lists the Common Shares, requires Member approval for the issuance of listed shares in a private transaction under the circumstances of such issuance.

        In evaluating the issuance of the Convertible Preference Shares, the Board determined that it was in your interest, as Members of the Company, to repay the Seller Note in full with cash, as opposed to Common Shares valued at $245.00 per share pursuant to the terms of the Note Purchase Option Agreement which governed the Seller Note. Under a capital structure devised by the Company, the Convertible Preference Shares, convertible into 677,966 Common Shares upon Member approval, were issued to Franklin in lieu of Common Shares. The Board would not have authorized the issuance of the Convertible Preference Shares if it had not believed the issuance of such securities in such circumstances was in the interest of the Company and its Members.

        The Company agreed to seek Member approval for the issuance of Common Shares upon the repurchase and cancellation of the Convertible Preference Shares at the 2003 Annual Meeting. Approval by a majority of the votes cast on this proposal will be required to approve the issuance,provided that a quorum is present, in person or by proxy, at the 2003 Annual Meeting. The principal terms of the Convertible Preference Shares appear at the end of this proposal.

        The Seller Note was repaid in full on November 29, 2002 and, accordingly, this proposal will have no effect on that transaction.

Consequences of the Vote

        Upon approval of this proposal, each Convertible Preference Share will be repurchased and cancelled by the Company in consideration of the issuance of one Common Share (the "Conversion"). Assuming Conversion, the number of outstanding Common Shares at March 21, 2003 would increase by approximately 8.1%.

        If the required affirmative vote by the members is not obtained, the Convertible Preference Shares will remain outstanding in accordance with their respective current terms. Those terms, as described below, provide that if the Members of the Company have not voted to approve the Conversion by March 31, 2005, Franklin will have the right to receive cash, at the then market value of Common Shares, in lieu of Common Shares upon any Conversion.

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Reasons for the Board's Recommendation

        The Board believes that the Conversion benefits existing members for the following reasons: (i) Conversion eliminates the liquidation preference holders of Convertible Preference Shares have over holders of Common Shares; (ii) Conversion eliminates the dividend requirement of $2.95 annually per Convertible Preference Share; (iii) disapproval of the Conversion does not benefit holders of Common Shares as the Convertible Preference Shares derive the same economic benefit from any increase in the value of the Company's Common Shares; and (iv) although the Convertible Preference Shares do not enjoy general voting rights, the Board believes that this voting disadvantage is balanced by the special voting rights described below. The Board does recognize that the Convertible Preference Shares are not listed on the Exchange and have no established market. As such they may be less liquid than Common Shares; however, this possible difference is not likely to produce a benefit for holders of Common Shares since they can be redeemed for cash after March 31, 2005 in their current form.

        As described above, absent Member approval, the Company may be required to pay cash for any Convertible Preference Shares Converted after March 31, 2005 at the then market value of the Company's Common Shares, or upon the redemption of the Convertible Preference Shares on October 31, 2012 at $295.00 per share. Conversions or redemptions for cash could create a strain on the Company's cash resources which could, in turn, hinder the payment of cash dividends to holders of Common Shares. Further, if the Company were to borrow additional monies for such redemptions, the Company's debt to equity ratio could increase to a level higher than the Company prefers to operate. Finally, any cash used to convert or redeem the Convertible Preference Shares would not be available for other corporate purposes.

Convertible Preference Shares

        The following summarizes the principal features of the Convertible Preference Shares:

        Dividends.    Holders of Convertible Preference Shares, when and as declared by the Board out of the net profits or net assets of the Company legally available for payment under Bermuda Law, are entitled to receive cumulative dividends payable in cash at the annual rate of $2.95 per share, payable semi-annually beginning on December 31, 2002. Past due and unpaid dividends will accrue an additional dividend at an annual rate of 1% compounded each year. The Company will not declare or pay dividends on its Common Shares as long as dividends on the Convertible Preference Shares are past due and unpaid.

        Conversion.    Upon receipt of Member approval, Conversion will occur at a conversion price of $295.00 per share, subject to certain standard anti-dilution adjustments for issuances of and distributions on Common Shares. The conversion price represents a $30 discount to the closing market price for the Common Shares on October 23, 2002, the day Franklin committed to purchase such shares. After March 31, 2005, and absent Member approval, each Convertible Preference Share is convertible into cash equal to the then fair market value of each Common Share.

        Redemption.    Any Convertible Preference Shares outstanding on October 31, 2012 will be redeemed by the Company for $295.00 in cash per share, plus all accrued dividends as of such date.

        Voting.    The holders of the Convertible Preference Shares have no voting rights except for any voting rights provided in the Company's Bye-laws or required by the Companies Act 1981. In addition, the Company shall not amend, alter or repeal its Memorandum of Continuance, Bye-laws or the terms and conditions of the Convertible Preference Shares in a manner that adversely affects the rights of the Convertible Preference Shares or increases the authorized number of Convertible Preference Shares without first obtaining the consent or approval of at least two-thirds of the then-outstanding Convertible Preference Shares.

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        Liquidation.    In the event of any liquidation, dissolution, or winding up of the Company, holders of the Convertible Preference Shares are entitled to receive payment of $50.00 per share plus all accrued dividends before any distribution is made to holders of Common Shares.

        Restrictions on Transfer.    Convertible Preference Shares can only be transferred, except to the extent required by applicable law, (i) with the prior written consent of the Company, which consent shall not be unreasonably withheld, (ii) by any initial holder to one of its affiliates or (iii) to the Company or any initial holder of Convertible Preference Shares. The Convertible Preference Shares have not been registered under the Securities Act of 1933 and may not be offered or sold in the United States or to any citizen or resident of the United States in absence of a valid registration of the Securities Act of 1933 except in reliance on an exemption from the registration requirements. Additionally, transfers of Convertible Preference Shares may also be subject to approval of the Bermuda Monetary Authority.

        Registration Rights.    Subject to certain limitations, holders of the Convertible Preference Shares are entitled to demand registration rights and piggyback rights for the registration of the Common Shares issued upon Conversion.

The Board recommends a vote FOR Proposal 4 approving the issuance of additional Common Shares upon conversion of Convertible Preference Shares.


PROPOSAL 5

TECHNICAL AMENDMENTS TO THE BOARD RECOMMENDSLONG-TERM INCENTIVE PLAN

        Members are being asked to approve certain technical amendments to the Company's Long-Term Incentive Plan at the 2003 Annual Meeting. The proposed amendments do not increase the number of Common Shares that may be issued under the Incentive Plan in the future. The Incentive Plan was adopted by the Board and approved by the Company's sole shareholder in 1985 and subsequently amended by its shareholders in 1995 and by its Members in 2001. On February 24, 2003, the Compensation Committee approved, subject to the approval of the Company's Members, a series of technical amendments to the Incentive Plan to: (i) create a currency, known as performance units, that is able to track the growth in value of a particular business unit, such as a subsidiary of the Company, (ii) to impose an annual limit on the number of performance shares that can be granted in a given year to any one individual and (iii) to include the Company's measure of intrinsic value per share as an additional performance objective.

Background

        The Company believes that long-term compensation should be based on "pay for performance" and further believes that management should act as if they were owners. With these objectives in mind, the Committee believes that the proposed amendments to the Incentive Plan will allow the Company to continue to closely align the financial interests of management with those of the Company's Members. This summary of the material terms of the Incentive Plan is qualified in its entirety by reference to Appendix I attached to this Proxy Statement.

Description of the Incentive Plan

        Awards.    As amended, the Incentive Plan provides for the grant of performance shares, performance units, options, stock appreciation rights and shares of restricted stock.

        Administration.    The Compensation Committee of the Company's Board of Directors administers the Incentive Plan and has the authority to select employees to receive awards under the Incentive Plan, determine the type, size and terms of awards granted under the Incentive Plan, interpret the

25



Incentive Plan and related awards and establish, amend and rescind rules and regulations relating to the Incentive Plan.

        Shares.    As approved by the Board and the Company's Members in 2001, a maximum of 300,000 Common Shares, par value $1.00 (subject to adjustment as provided in the Incentive Plan), may be issued under the Incentive Plan. The proposed amendments do not increase the number of Common Shares that may be issued under the Incentive Plan in the future. As of December 31, 2002, 234,000 Common Shares were still available for issuance under the Incentive Plan. As of the close of trading on March 21, 2003, the value of a Common Share was $339.50.

        Eligibility.    Any key employee of the Company or any of its subsidiaries designated by the Compensation Committee is eligible to receive an award under the Incentive Plan. As of the date of this Proxy Statement, the Company believes the number of key employees of the Company and its subsidiaries is approximately twenty.

        Performance Shares and Performance Units.    Performance shares are awards of phantom shares of the Company's Common Shares, some or all of which are earned if performance goals established by the Compensation Committee at the time of grant are satisfied over a specified award period. The value earned by an employee pursuant to an award of performance shares is generally equal to the number of award shares earned with respect to the award period multiplied by the fair market value of a Common Share on the date of payment. Performance shares are typically paid in cash, though they may be paid in Common Shares at the election of the Compensation Committee. The maximum amount of compensation that can be earned by an employee pursuant to an award of performance shares with respect to any particular award period of one year or more cannot exceed the value of 50,000 Common Shares.

        As amended, the Incentive Plan also provides for the grant of performance units. Performance units are awards of phantom units that are paid out if performance goals established by the Compensation Committee at the time of grant are satisfied over a specified award period. The value earned by an employee pursuant to an award of performance units is equal to the number of performance units earned over the award period multiplied by the unit value determined by the Compensation Committee, which is $100 increased by the percentage growth in value of the Company, any of its subsidiaries or any combination thereof over the award period. The maximum amount of compensation that can be earned by an employee with respect to an award of performance units during any award period of three years or more cannot exceed $10,000,000. This limit on the amount of compensation that can be earned with respect to performance units is prorated for award periods of less than three years.

        Awards of performance shares and performance units are forfeited if any employee terminates employment with the Company and its subsidiaries prior to the end of the award period for any reason other than death, disability or retirement.

        The performance goals that may be selected by the Compensation Committee with respect to performance share and performance unit awards are based upon one or more of the following criteria: (i) consolidated earnings before or after taxes (including earnings before interest, taxes, depreciation and amortization); (ii) net income; (iii) operating income; (iv) earnings per share; (v) book value per share; (vi) return on shareholders' equity; (vii) expense management; (viii) return on investment; (ix) improvements in capital structure; (x) share price; (xi) combined ratio; (xii) operating ratio; (xiii) profitability of an identifiable business unit or product; (xiv) maintenance or improvement of profit margins; (xv) market share; (xvi) revenues or sales; (xvii) costs; (xviii) cash flow; (xix) working capital; (xx) return on assets; (xxi) customer satisfaction; (xxii) employee satisfaction; and (xxiii) economic value per share (computed based on book value per share determined in accordance with generally accepted accounting principles ("GAAP") adjusted for changes in the intrinsic value of

26



assets and liabilities whose value differs from their GAAP carrying value). The foregoing criteria may, as determined by the Compensation Committee, relate to the Company, one or more of its subsidiaries or divisions, units, partnerships, joint ventures, minority investments, product lines or products, or any combination of the foregoing and may be applied on an absolute basis and/or be relative to one or more peer companies or indices or any combination thereof. At the time of an award of performance shares or performance units, the Compensation Committee establishes specific performance objectives that must be achieved with respect to the selected performance goal over the specified award period to earn some or all of a performance share or performance unit award. The Compensation Committee may calculate the relevant performance objective without regard to extraordinary items.

        The Compensation Committee may settle performance share or performance unit awards earned by an employee in cash or Common Shares and may elect to defer any such settlement to a later date.

        Options and Stock Appreciation Rights.    Options granted under the Incentive Plan may be non-qualified options or incentive stock options and are granted to eligible employees for no consideration. Options may be granted in tandem with stock appreciation rights or performance shares. An employee cannot receive options and stock appreciation rights on more than 10,000 Common Shares during any one year.

        The exercise price of each Common Share covered by an option will be not less than the greater of the fair market value of a Common Share as of the date the option is granted or the par value of a Common Share, provided that the exercise price of each Common Share of an incentive share option granted to certain employees with large shareholdings in the Company cannot be less than 110% of the fair market value of a Common Share on the date the option is granted. Each option becomes vested and exercisable at such times and subject to such terms and conditions as the Compensation Committee may, in its sole discretion, specify in the option agreement. Except in the event of an optionholder's death, disability or retirement or except as determined by the Board, each option will expire immediately, without any payment, upon the earlier of (1) the tenth anniversary of the option's grant date and (2) three months after the holder's termination of employment. Common Shares will not be delivered pursuant to an option's exercise until the optionholder pays the exercise price in full. Payment of the exercise price may be made in cash or check, by exchanging Common Shares owned by the optionholder or a combination of these methods.

        There are no federal tax consequences to optionholders, the Company or its subsidiaries in connection with the grant of an option. Upon the exercise of non-qualified options, optionholders will generally be subject to federal taxation on the aggregate difference in value between the option exercise price and the fair market value of the Common Shares with respect to which the option is exercised. That amount should be deductible for federal tax purposes with respect to employees of subsidiaries of the Company that are incorporated in the United States. A VOTEholder of an incentive stock option is generally not subject to federal taxation, and the Company and its subsidiaries are generally not entitled to a deduction, upon its exercise if the Common Shares obtained upon exercise are held for a specified period of time. Because the Company is incorporated in Bermuda, it cannot take a federal tax deduction for options exercised by its employees.

        Options on a total of 81,000 Common Shares have been granted under the Incentive Plan, all of which were issued in a one-time award in February 2000. The outstanding Options were granted at an exercise price equal to the underlying market value of Common Shares on the date of grant and vest 10% per year through 2009. The exercise price escalates on a straight-line basis by 6% per annum over the ten-year life of the options. Those options were granted to employees of the Company and its subsidiaries as follows: Raymond Barrette, President and Chief Executive Officer of the Company, 9,000; Steven E. Fass, President and Chief Executive Officer of Folksamerica, 9,000; David Staples, 9,000; Reid Campbell, 9,000; Kernan Oberting, 9,000; Michael Paquette, 9,000; Michael Tyburski, 9,000; and all other employees of the Company and its subsidiaries as a group, 18,000. As of March 21, 2003,

27



options on 56,265 Common Shares were still outstanding, options on 17,535 Common Shares have been exercised and options on 7,200 Common Shares have been forfeited.

        Stock appreciation rights can only be granted in tandem with options and give the holder the right to receive, in exchange for the cancellation of the option on the number of Common Shares with respect to which the stock appreciation right is exercised, a payment in an amount equal to the aggregate difference between the applicable exercise price and the fair market value of Common Shares with respect to which the right is exercised (which for this purpose only cannot exceed 150% of the applicable exercise price). Stock appreciation rights may be settled in cash or Common Shares.

        Restricted Stock.    The Compensation Committee may award shares of restricted stock, which are Common Shares that may not be sold, assigned, transferred, pledged, hypothecated or otherwise disposed of during a period designated by the Compensation Committee (the "restricted period"). The Company may purchase the Common Shares subject to an award of Restricted Stock at any price specified by the Compensation Committee at the time of grant if the holder's employment with the Company terminates before the end of the applicable restricted period for a reason other than death, disability or, in the discretion of the Board, retirement or other voluntary termination.

        Change in Control.    In the event of an "unfriendly change in control" (as defined in the Incentive Plan), all options generally become immediately vested and exercisable.

        In the event of certain terminations of an employee's employment with the Company or certain adverse changes to the Incentive Plan, in each case within 24 months of a "change in control" (as defined in the Incentive Plan), all options held by the employee immediately vest and become exercisable, awards of restricted stock held by the employee immediately vest and become unrestricted and the employee becomes entitled to a payment (as specified in the Incentive Plan) with respect to performance share or performance unit awards granted prior to the change in control.

        Certain Transactions.    The Compensation Committee may make equitable changes in the terms of outstanding awards granted under the Incentive Plan or in the number of Common Shares issuable under an award or under the Incentive Plan in the event of any change in the Company's outstanding Common Shares by reason of any stock split, stock dividend, recapitalization, merger, consolidation, reorganization, combination or exchange of Common Shares or other similar event.

        Amendment.    The Board may amend the Incentive Plan at any time, but no such amendment may, without the approval of the Company's Members (except as described in Certain Transactions, above) increase the number of Common Shares that may be issued under the Incentive Plan or change the class of employees eligible to participate in the Incentive Plan.

        Limitation on Company's Deduction.    Under Section 162(m) of the Code, the federal tax deduction for subsidiaries of the Company that are incorporated in the United States for all compensation paid to the Company's chief executive officer and certain other highly paid executive officers of the Company or its subsidiaries in any one year is limited to $1,000,000 per officer. Compensation that qualifies as performance-based compensation is exempt from this deduction limitation. White Mountains believes that the federal tax deductions arising from an officer's exercise of options or stock appreciation rights and amounts earned by an officer pursuant to performance share or performance unit awards should be exempt from this limitation. However, it is possible that in certain circumstances deductions arising from these awards would be subject to disallowance under Section 162(m) of the Code.

        A complete copy of the Incentive Plan, reflecting the proposed amendments thereto, has been provided herein as Appendix I.The Board recommends a vote FOR Proposal 5 which calls for approval of the technical amendments to the Incentive Plan.

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PROPOSAL 3 WHICH CALLS FOR THE ELECTION OF MESSRS. KEMP AND FASS TO ANY NEW NON-UNITED STATES OPERATING SUBSIDIARIES. PROPOSAL 4 6

APPROVAL OF THE APPOINTMENT OF INDEPENDENT AUDITOR

        Subject to Member approval, the Audit Committee of the Board has appointed PricewaterhouseCoopers LLP ("PwC") as White Mountains' Independent Auditor for 2002.2003. Further, Members are being asked to authorize the Board, acting through the Audit Committee, to negotiate and fix the remuneration to be paid to PwC in connection with the services to be provided to the Company for 2003. Representatives from PwC will attend the 20022003 Annual Meeting, will be provided with the opportunity to make a statement and will be available to answer appropriate questions.

        PwC has served as the Company's Independent Auditor for three years, as Folksamerica's Independent Auditor for more than 20 years, and as OneBeacon's Independent Auditor for more than 25 years. THE BOARD RECOMMENDS A VOTE

The Board recommends a vote FOR PROPOSAL 4 APPROVING THE APPOINTMENT OF PWC AS WHITE MOUNTAINS' INDEPENDENT AUDITOR FOR 2002. 18 Proposal 6 approving the appointment of PwC as White Mountains' Independent Auditor for 2003.


OTHER MATTERS MANNER OF VOTING PROXIES

Manner of Voting Proxies

        Common Shares represented by all valid proxies received will be voted in the manner specified in the proxies. Where specific choices are not indicated, the Common Shares represented by all valid proxies received will be voted FOR each of the proposals named earlier in this Proxy Statement.

        Should any matter not described above be acted upon at the meeting, the persons named in the proxy card will vote in accordance with their judgment. The Board knows of no other matters which are to be considered at the 20022003 Annual Meeting. VOTES REQUIRED FOR APPROVAL The

Votes Required for Approval

        Unless indicated otherwise above, the proposals require the affirmative vote of a majority of the voting power held by holders of Common Shares present at the 20022003 Annual General Meeting, in person or by proxy, provided a quorum is present. INSPECTORS OF ELECTION

Inspectors of Election

        EquiServe Trust Company, of New York,N.A., P.O. Box 2500, Jersey City, New Jersey 07303-2500,43069, Providence, Rhode Island 02940-3069, has been appointed as Inspectors of Election for the 20022003 Annual Meeting. Representatives of EquiServe will attend the 20022003 Annual Meeting to receive votes and ballots, supervise the counting and tabulating of all votes and ballots, and determine the results of the vote. COSTS OF SOLICITATION

Costs of Solicitation

        The solicitation of proxies will be made primarily by mail, however, directors, officers, employees and agents of the Company may also solicit proxies by telephone, telegram or personal interview. Solicitation costs will be paid by the Company. Upon request, the Company will reimburse banks, brokerage houses and other custodians, nominees and fiduciaries for their reasonable expenses incurred in forwarding proxy materials to their principals. AVAILABLE INFORMATION

Available Information

        The Company is subject to the informational reporting requirements of the Exchange Act of 1934. In accordance therewith, the Company files reports, proxy statements and other information with the SEC. THE COMPANY WILL PROVIDE TO EACH PERSON TO WHOM A COPY OF THIS PROXY STATEMENT IS DELIVERED, UPON REQUEST AND WITHOUT CHARGE, COPIES OF ALL DOCUMENTS (EXCLUDING EXHIBITS UNLESS SPECIFICALLY REQUESTED) FILED BY THE COMPANY WITH THEThe Company will provide to any Member, upon request and without charge, copies of all

29



documents (excluding exhibits unless specifically requested) filed by the Company with the SEC. Written or telephone requests should be directed to the Corporate Secretary, White Mountains Insurance Group, Ltd., 28 Gates80 South Main Street, White River Junction, Vermont, 05001,Hanover, New Hampshire, 03755, telephone number (802) 295-4500.(603) 640-2200. Additionally, all such documents are physically available at the Company's registered office at Clarendon House, 2 Church Street, Hamilton, HM DX Bermuda. OFFICES OF THE COMPANY11 Bermuda and are available for viewing atwww.whitemountains.com shortly after such material is electronically filed with or furnished to the SEC.

Offices of the Company

        The Company's headquarters is located at Crawford House, 23 Church Street, Hamilton, HM 11, Bermuda (with a mailing address of 12 Church Street, Suite 322, Hamilton HM 11, Bermuda), its principal executive office is located at 28 Gates80 South Main Street, White River Junction, Vermont, 05001,Hanover, New Hampshire, 03755, and its registered office is located at Clarendon House, 2 Church Street, Hamilton, HM 11, Bermuda. www.whitemountains.com All reports, including press releases, SEC filings and other information relating to White Mountains are available

Proposals by Members for viewing or download at our website. PROPOSALS BY MEMBERS FOR THE 2003 ANNUAL MEETING OF MEMBERSthe 2004 Annual Meeting of Members

        Member proposals (other than those proposals to nominate persons as directors) must be received in writing by the Secretary of the Company no later than December 31, 200211, 2003 and must comply with the requirements of the SEC in order to be considered for inclusion in the Company's proxy statement relating to the Annual Meeting to be held in 2003. 2004.

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Appendix I

White Mountains
Long-Term
Incentive Plan
(as amended)

1.    PURPOSE

        The undersigned hereby appoints K. Thomas Kemppurpose of the White Mountains Long-Term Incentive Plan (the "Plan") is to advance the interests of White Mountains Insurance Group, Ltd. (the "Company") and Gordon S. Macklin,its stockholders by providing long-term incentives to certain key executives of the Company and each of them, proxiesits subsidiaries.

2.    ADMINISTRATION

        The Plan shall be administered by the Compensation Committee (the "Committee") of the Board of Directors (the "Board") of the Company. No member of the Committee shall be an employee of the Company or a subsidiary of the Company or shall have been eligible within one year prior to his appointment to receive awards under the Plan ("Awards") or to receive awards under any other plan of the Company or its subsidiaries under which participants are entitled to acquire stock, stock options or stock appreciation rights of the Company or any of its subsidiaries.

        The Committee shall have exclusive authority to select the employees to be granted Awards, to determine the type, size and terms of the Awards and to prescribe the form of the instruments embodying Awards. The Committee shall be authorized to interpret the Plan and the Awards granted under the Plan, to establish, amend and rescind any rules and regulations relating to the Plan and to make any other determinations which it believes necessary or advisable for the administration of the Plan. The Committee may correct any defect or supply any omission or reconcile any inconsistency in the Plan or in any Award in the manner and to the extent the Committee deems desirable to carry it into effect. Any decision of the Committee in the administration of the Plan, as described herein, shall be final and conclusive. The Committee may act only by a majority of its members in office, except that the members thereof may authorize any one or more of their number or any officer of the Company to execute and deliver documents on behalf of the Committee. No member of the Company shall be liable for anything done or omitted to be done by him or by any other member of the Committee in connection with fullthe Plan, except for his own willful misconduct or as expressly provided by statute.

3.    PARTICIPATING SUBSIDIARIES

        If a subsidiary of the Company wishes to participate in the Plan and its participation shall have been approved by the Board, the Board of Directors of the subsidiary shall adopt a resolution in form and substance satisfactory to the Committee authorizing participation by the subsidiary in the Plan. As used herein, "subsidiary" shall mean a "subsidiary corporation" as defined in Section 424 (f) of the Internal Revenue Code of 1986, as amended (the "Code").

        A subsidiary may cease to participate in the Plan at any time by action of the Board or by action of the Board of Directors of such subsidiary, which latter action shall be effective not earlier than the date of delivery to the Secretary of the Company of a certified copy of a resolution of the subsidiary's Board of Directors taking such action. Termination of participation in the Plan shall not relieve a subsidiary of any obligations theretofore incurred by it under the Plan.

4.    AWARDS



(1)  Actual number will be the number of Shares remaining in inventory at the time the LTIP is submitted to shareholders.

5.    STOCK OPTIONS AND STOCK APPRECIATION RIGHTS

        The Committee may grant Stock Options (including, in its discretion, Stock Appreciation Rights) either alone or, as provided in paragraph 7, in conjunction with Performance Shares. A maximum of 10,000 Stock Options and Stock Appreciation Rights (not including Stock Appreciation Rights attached to Stock Options) may be issued in one year to an employee. Each Stock Option shall comply with the following terms and conditions:

2


3


4


5


6.    RESTRICTED STOCK

        Each Award of Restricted Stock shall comply with the following terms and conditions:

6


7


7.    PERFORMANCE SHARES

        The Award of Performance Shares to a participant will entitle him to receive, without payment to the Company, all or part of a specified amount (the "Actual Value") determined by the Committee, if the terms and conditions specified herein and in the Award are satisfied. Payment in respect of an Award shall be made as provided in subparagraph 7(e). Each Award of Performance Shares shall be subject to the following terms and conditions:

8


9


10


8.    PERFORMANCE UNITS

        The Award of Performance Units to a participant will entitle him to receive, without payment to the Company, all or part of a specified amount (the "Actual Value") determined by the Committee, if the terms and conditions specified herein and in the Award are satisfied. Payment in respect of an Award shall be made as provided in subparagraph 8(e). Each Award of Performance Units shall be subject to the following terms and conditions:

11


12


13


14


9.    DISABILITY

        For the purposes of this Plan, a participant shall be deemed to be disabled if the Committee shall determine that the physical or mental condition of the participant is such as would entitle him to payment of monthly disability benefits under any disability plan of the Company or a subsidiary in which he is a participant.

10.  RELATED EMPLOYMENT

        For the purposes of this Plan, Related Employment shall mean the employment of an individual by an employer which is neither the Company nor a subsidiary provided: (i) such employment is undertaken by the individual and continued at the request of the Company or a subsidiary; (ii) immediately prior to undertaking such employment, the individual was an officer or employee of the Company or a subsidiary, or was engaged in Related Employment as herein defined; and (iii) such employment is recognized by the Committee, in its sole discretion, as Related Employment for the purposes of this paragraph 10. The death or disability of an individual during a period of Related Employment as herein defined shall be treated, for purposes of this Plan, as if the death or onset of disability had occurred while the individual was an officer or employee of the Company.

11.  CHANGE IN CONTROL

15


12.  TERMINATION WITHOUT CAUSE

        For purposes of this Plan, "Termination Without Cause" shall mean a termination of the participant's employment with the Company or a subsidiary by the Company or the subsidiary other than (i) for disability as described in paragraph 9 or (ii) for Cause." "Cause" shall mean (a) an act or omission by the participant that constitutes a felony or any crime involving moral turpitude; or (b) willful gross negligence or willful gross misconduct by the participant in connection with his employment by the Company or by a subsidiary which causes, or is likely to cause, material loss or damage to the Company. Notwithstanding anything herein to the contrary, if the participant's employment with the Company or one of its subsidiaries shall terminate due to a Change in Control of the Company as described in Subsection 11(a)(iii), where the purchaser, as described in such subsection, formally assumes the Company's obligations under this Plan or places the participant in a similar or like plan with no diminution of the value of the awards, such termination shall not be deemed to be a "Termination Without Cause."

13.  CONSTRUCTIVE TERMINATION

        "Constructive Termination" shall mean a termination of employment with the Company or a subsidiary at the initiative of the participant that the participant declares by prior written notice delivered to the Secretary of the Company to be a Constructive Termination by the Company or a subsidiary and which follows (a) a material decrease in his salary or (b) a material diminution in the authority, duties or responsibilities of his position with the result that the participant makes a determination in good faith that he cannot continue to carry out his job in substantially the same manner as it was intended to be carried out immediately before such diminution. Notwithstanding anything herein to the contrary, Constructive Termination shall not occur within the meaning of this meetingparagraph 13 until and unless 30 days have elapsed from the date the Company receives such written notice without the Company curing or causing to be cured the circumstance or circumstances described in this paragraph 13 on the basis of which the declaration of Constructive Termination is given.

16



14.  ADVERSE CHANGE IN THE PLAN

        An "Adverse Change in the Plan" shall mean

15.  DILUTION AND OTHER ADJUSTMENTS

        In the event of any change in the Outstanding Shares of the Company by reason of any stock split, stock dividend, recapitalization, merger, consolidation, reorganization, combination or exchange of Shares or other similar event, and if the Committee shall determine, in its sole discretion, that such change equitably requires an adjustment in the number or kind of Shares that may be issued under the Plan pursuant to subparagraph 4(b), in the number or kind of Shares subject to, or the Stock Option price per share under, any outstanding Stock Option, in the number or kind of Shares which have been awarded as Restricted Stock or in the repurchase option price per share relating thereto, in the number of Maximum Value or Actual Value of Performance Shares which have been awarded to any participant, or in any measure of performance, then such adjustment shall be made by the Committee and shall be conclusive and binding for electionall purposes of the Plan.

16.  DESIGNATION OF BENEFICIARY BY PARTICIPANT

        A participant may name a beneficiary to terms endingreceive any payment to which he may be entitled in 2005. John J. Byrne George J. Gillespie, III Frank A. Olson Mark J. Byrne John D. Gillespie Your voterespect of Performance Shares or Performance Units under the Plan in the event of his death, on a form to be provided by the Committee. A participant may change his beneficiary from time to time in the same manner. If no designated beneficiary is living on the date on which any amount becomes payable to a participant's executors or administrators, the term "beneficiary" as used in the Plan shall include such person or persons.

17.  MISCELLANEOUS PROVISIONS

17


18.  AMENDMENT

        The Plan may be amended at any time and from time to time by the Board, but no amendment which increases the aggregate number of Shares which may be issued pursuant to the Plan or the class of employees eligible to participate shall be effective unless and until their resignation or removal from office. K. Thomas Kemp Anders Henriksson Elinor M. Lucas (alt.) Steven E. Fass Sheila E. Nicoll Your vote for the electionsame is approved by the shareholders of the directorsCompany. No amendment of the Plan shall adversely affect any right of any new non-United States subsidiary mayparticipant with respect to any Award previously granted without such participant's written consent.

19.  TERMINATION

        This Plan shall terminate upon the earlier of the following dates or events to occur:

18


20.  SHAREHOLDER ADOPTION

        The Plan shall be indicated onsubmitted to the reverse side.shareholders of the Company for their approval or adoption. The following directors are being nominated to servePlan shall not be effective and no Award shall be made hereunder unless and until their resignation or removal from office. K. Thomas Kemp Steven E. Fass (Change of address/comments) - -------------------------------------------------------------------------------- - -------------------------------------------------------------------------------- - -------------------------------------------------------------------------------- - -------------------------------------------------------------------------------- (If you have writtenthe Plan has been so approved and adopted by the shareholders in the above space, please markmanner required by the corresponding boxlaws of Bermuda and the State of Delaware.

19


P
R
O
X
Y
WHITE MOUNTAINS INSURANCE GROUP, LTD.

Proxy Solicited on Behalf of the Board of Directors of

the Company for the Annual General Meeting to be Held May 19, 2003
The undersigned hereby appoints Raymond Barrette and John D. Gillespie, and each of them, proxies with full power of substitution, to vote all Common Shares of the undersigned at the 2003 Annual General Meeting of Shareholders to be held May 19, 2003, and at any adjournment thereof, upon all subjects that may properly come before the meeting including the matters described in the proxy statement furnished herewith, subject to any directions indicated on the reverse of this card or below. If no directions are given, the proxies will vote FOR the Election of the Company's Directors, FOR the Election of Directors of Fund American Re., FOR the Election of Directors to any New Non-United States Operating Subsidiaries, FOR the Issuance of Common Shares Upon Conversion of Convertible Preference Shares, FOR Technical Amendments to the Long-Term Incentive Plan, FOR Approval of the Appointment of Independent Auditor, and at their discretion on any other matter that may properly come before the meeting.

Your vote for the Election of the Company's Directors may be indicated on the reverse side. The following Directors are being nominated at this meeting for election to terms ending in 2006.



(Change of address/comments)



        Raymond Barrette        Howard L. Clark, Jr.
        Robert P. Cochran        Arthur Zankel



Your vote for the election of Fund American Re's directors may be indicated on the reverse side. The following directors are being nominated to serve until their resignation or removal from office.


(If you have written in the above space, please mark the
corresponding box on the reverse side of this card.)

Raymond Barrette


Anders Henriksson


Elinor M. Lucas (alt.)


Steven E. FassSheila E. Nicoll

Your vote for the election of the directors of any new non-United States subsidiaries may be indicated on the reverse side. The following directors are being nominated to serve until their resignation or removal from office.
        Raymond Barrette        Steven E. Fass



Your vote is important! Please sign and date on the reverse side and return promptly in the enclosed postage-paid envelope or otherwise to White Mountains Insurance Group, Ltd., c/o EquiServe Trust Company, Post Office Box 8085, Edison, New Jersey 08818-9052.




PLEASE RETURN THIS PROXY PROMPTLY IN THE ENCLOSED ENVELOPESEE REVERSE SIDE

ý
Please mark your
votes as in this
example.

This proxy when properly executed will be voted in the manner directed herein. If no directions are made, this proxy will be voted FOR the electionProposals 1, 2, 3, 4, 5 and 6.

The Board of Directors recommends a vote "FOR" Proposals 1, 2, 3, 4, 5 and 6.
  FORWITHHELD  FORWITHHELD  FORWITHHELD  FORAGAINSTABSTAIN
1.Election of Company Directorsoo2.Election of Directors of Fund American Reoo3.Election of Directors to any New Non-US Subsidiariesoo4.Issuance of Common Sharesooo

FOR, except vote withheld from the following nominee(s):

FOR, except vote withheld from the following nominee(s):

FOR, except vote withheld from the following nominee(s):

 

 

FOR

AGAINST

ABSTAIN
 
 
 
5.Technical Amendments to the Long-Term Incentive Planooo

 

 

 

 

 

 

 

 

Change of Address

 

 

 

FOR

AGAINST

ABSTAIN
        Comments on Reverse Sideo6.Appointment of Independent Auditorsooo



The signer hereby revokes all proxies heretofore given by the signer to vote at said meeting or any adjournment thereof.



Please sign exactly as name appears hereon. Joint owners should each sign. When signing as attorney, executor, administrator, trustee or guardian, please give full title as such.








SIGNATURE(S)DATE



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Table of the Company's directors,Contents
WHITE MOUNTAINS INSURANCE GROUP, LTD. NOTICE OF 2003 ANNUAL GENERAL MEETING OF MEMBERS TO BE HELD MAY 19, 2003
WHITE MOUNTAINS INSURANCE GROUP, LTD. PROXY STATEMENT
PROCEDURES FOR the electionNOMINATING DIRECTORS
VOTING SECURITIES AND PRINCIPAL HOLDERS THEREOF Voting Rights of Fund American Re's directors,Members
Principal Holders of Common Shares
Beneficial Stock Ownership of Directors and Executive Officers
COMPENSATION OF DIRECTORS
COMPENSATION OF EXECUTIVE OFFICERS Summary Compensation Table
Option Grants in Last Fiscal Year
Aggregated Option Exercises in Last Fiscal Year and Fiscal Year-End Option Values
Long-Term Incentive Plans—Awards in Last Fiscal Year
Equity Compensation Plan Table
COMPENSATION PLANS
REPORTS OF THE COMMITTEES ON EXECUTIVE COMPENSATION
REPORT OF THE AUDIT COMMITTEE
FEES BILLED BY THE COMPANY'S INDEPENDENT AUDITOR FOR the election of the directors of any new non-United States subsidiary, and FOR the approval of the appointment of PricewaterhouseCoopers as Independent Auditor for 2002.
- ------------------------------------------------------------------------------------------------------------------------------------ The Board of Directors recommends a vote "FOR" Proposals 1, 2, 3 and 4. - ------------------------------------------------------------------------------------------------------------------------------------ FOR WITHHELD FOR WITHHELD FOR WITHHELD FOR AGAINST ABSTAIN 1. Election 2. Election of 3. Election of the 4. Approval of of Company / / / / directors of / / / / directors of / / / / Independent / / / / / / directors Fund American Re any new non-US Auditors subsidiary FOR, except vote withheld(?) FOR, except vote withheld FOR, except vote withheld from Change of Address the following nominee(s) from the following nominee(s): the following nominee(s): Comments on Reverse Side / / - ---------------------------- ------------------------------ ------------------------------- - ------------------------------------------------------------------------------------------------------------------------------------
The signer hereby revokes all proxies heretofore given by the signer to vote at said meeting or any adjournment thereof. Please sign exactly as name appears hereon. Joint owners should each sign. When signing as attorney, executor, administrator, trustee or guardian, please give full title as such. ------------------------------------------------- ------------------------------------------------- SIGNATURE(S) DATE
SERVICES PERFORMED IN 2002
MEMBER RETURN GRAPH
COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION IN COMPENSATION DECISIONS
COMPLIANCE WITH SECTION 16(a) OF THE EXCHANGE ACT
PROPOSAL 2 ELECTION OF DIRECTORS OF FUND AMERICAN RE
PROPOSAL 3 ELECTION OF DIRECTORS TO ANY NEW NON-UNITED STATES OPERATING SUBSIDIARIES
PROPOSAL 4 ISSUANCE OF COMMON SHARES UPON CONVERSION OF CONVERTIBLE PREFERENCE SHARES
PROPOSAL 5 TECHNICAL AMENDMENTS TO THE LONG-TERM INCENTIVE PLAN
PROPOSAL 6 APPROVAL OF THE APPOINTMENT OF INDEPENDENT AUDITOR
OTHER MATTERS