SEC Filing | White Mountains Insurance Group

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

FORM 11-K

(Mark One)
ý	Annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934 for the fiscal year ended December 31, 2003
OR
o	Transition report pursuant to Section 15(d) of the Securities Exchange Act of 1934 for the transition period from to
Commission file number 1-8993

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

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

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

REQUIRED INFORMATION

The following Financial Statements and Schedule for the Plan and a Written Consent of Independent Registered Public Accounting Firm are filed with, and included in, this Report as Exhibits 99(a) and 99(b) hereto, respectively, as detailed below:

99(a)

Financial Statements and Schedule for the Plan consisting of:

1.: Report of Independent Registered Public Accounting Firm;
2.: Statements of Net Assets Available for Benefits as of December 31, 2003 and 2002;
3.: Statements of Changes in Net Assets Available for Benefits for the years ended December 31, 2003 and 2002;
4.: Notes to Financial Statements;
5.: Schedule of Assets Held at End of Year as of December 31, 2003;

99(b)

Consent of Independent Registered Public Accounting Firm

SIGNATURES

THE PLAN. Pursuant to the requirements of the Securities Exchange Act of 1934, the Benefits Committee has duly caused this annual report to be signed on its behalf by the undersigned, thereunto duly authorized.

		ONEBEACON INSURANCE SAVINGS PLAN (the "Plan")
Date: June 28, 2004		By:	/s/ THOMAS N. SCHMITT Senior Vice President, Human Resources (the Plan Administrator) and Member of the Benefits Committee

EXHIBIT INDEX

Exhibit	Description
99(a)	Financial statements for the Plan consisting of:
	6.	Report of Independent Registered Public Accounting Firm;
	7.	Statements of Net Assets Available for Benefits as of December 31, 2003 and 2002;
	8.	Statements of Changes in Net Assets Available for Benefits for the years ended December 31, 2003 and 2002;
	9.	Notes to Financial Statements;
	10.	Schedule of Assets Held at End of Year as of December 31, 2003;
99(b)	Consent of Independent Registered Public Accounting Firm.

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REQUIRED INFORMATION
SIGNATURES
EXHIBIT INDEX

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Exhibit 99(a)

OneBeacon Insurance Savings Plan

Financial Statements and Supplemental Schedule to
Accompany 2003 Form 5500
Annual Report of Employee Benefit Plan
Under ERISA of 1974
For the Years Ended December 31, 2003 and 2002

Index of Financial Statements and Supplemental Schedule

		Page(s)
Report of Independent Registered Public Accounting Firm		2
Statements of Net Assets Available for Benefits December 31, 2003 and 2002		3
Statements of Changes in Net Assets Available for Benefits For the years ended December 31, 2003 and 2002		4
Notes to Financial Statements		5-10
Supplemental Schedule *:
	Schedule of Assets (Held at End of Year) December 31, 2003	11-15

* Other schedules required by Section 2520.103-10 of the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974 have been omitted because they are not applicable.

Report of Independent Registered Public Accounting Firm

To the Participants and Administrator of
OneBeacon Insurance Savings Plan

In our opinion, the accompanying statements of net assets available for benefits and the related statements of changes in net assets available for benefits present fairly, in all material respects, the net assets available for benefits of OneBeacon Insurance Savings Plan (the "Plan") at December 31, 2003 and 2002, and the changes in net assets available for benefits for the years then ended in conformity with accounting principles generally accepted in the United States of America. These financial statements are the responsibility of the Plan's management. Our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

Our audits were conducted for the purpose of forming an opinion on the basic financial statements taken as a whole. The supplemental schedule of assets (held at end of year) at December 31, 2003 is presented for the purpose of additional analysis and is not a required part of the basic financial statements but is supplementary information required by the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. This supplemental schedule is the responsibility of the Plan's management. The supplemental schedule has been subjected to the auditing procedures applied in the audits of the basic financial statements and, in our opinion, is fairly stated in all material respects in relation to the basic financial statements taken as a whole.

/s/ PricewaterhouseCoopers LLP
Boston, Massachusetts
June 16, 2004

OneBeacon Insurance Savings Plan

Statements of Net Assets Available for Benefits
December 31, 2003 and 2002

				2003		2002
Assets
	Investments:
		Investments at fair value (Notes B,C,D,E)		$	379,716,089	$	338,146,120
		Loans to participants at fair value (Note A)			4,884,748		5,311,372

			Total Investments		384,600,837		343,457,492

	Receivables:
		Employer contributions			57,784		38,858
		Participant contributions			181,650		121,212

			Total Receivables		239,434		160,070

	Total Assets				384,840,271		343,617,562

Liabilities
	Accrued administrative expenses				56,128		—

			Total Liabilities		56,128		—

			Net Assets Available for Benefits	$	384,784,143	$	343,617,562

The accompanying notes are an integral part of these financial statements.

OneBeacon Insurance Savings Plan

Statements of Changes in Net Assets Available for Benefits
For the years ended December 31, 2003 and 2002

				2003		2002
Additions
	Investment income:
		Interest and dividend income (Notes C and D)		$	6,728,962	$	7,524,446
		Interest income, participant loans (Note A)			292,014		426,113
		Net appreciation/(depreciation) in fair value of investments (Note D)			56,319,241		(31,233,678	)

					63,340,217		(23,283,119	)
	Contributions:
		Employer			5,305,491		6,498,091
		Participant			15,367,060		14,884,759

					20,672,551		21,382,850
	Transfers in—rollovers				3,254,052		2,841,350
	Other increases				163		15,734

			Total additions		87,266,983		956,815
Deductions
	Benefits paid to participants				45,830,458		72,560,525
	Administrative expenses				269,944		219,472
	Miscellaneous				—		621

			Total deductions		46,100,402		72,780,618

Net increase (decrease) excluding transfer out					41,166,581		(71,823,803	)
Transfers out—(Note H)					—		(17,242,618	)

Net increase (decrease)					41,166,581		(89,066,421	)
Net Assets Available for Benefits:
	Beginning of year				343,617,562		432,683,983

	End of year			$	384,784,143	$	343,617,562

The accompanying notes are an integral part of these financial statements.

OneBeacon Insurance Savings Plan

Notes to Financial Statements

A. Description of the Plan

The following description of the OneBeacon Insurance Savings Plan ("Plan") provides only general information. Participants should refer to the Plan agreement for a more complete description of the Plan's provisions.

General

The Plan is a defined contribution plan covering substantially all employees of OneBeacon Insurance Company (the "Company"). It is subject to the provisions of the Employee Retirement Income Security Act of 1974 ("ERISA").

Eligibility

Employees who complete sixty days of continuous service are eligible to participate in the Plan. Eligible employees are automatically enrolled in the Plan at a 2 percent contribution rate, unless waived by the employee.

Contributions

During 2002, the maximum participants could contribute each year was 18 percent of annual compensation on a pre-tax and/or an after-tax basis, as defined in the Plan. Effective January 1, 2003, participants could contribute 40 percent of annual compensation on a pre-tax and/or an after-tax basis. Participants direct their contributions into various investment options offered by the Plan. During 2002, the Company contributed on behalf of the participant 100 percent of the first 2 percent and 50 percent of the next 4 percent of base compensation that a participant contributes to the Plan. Effective January 1, 2003, the Company contributes 50 percent of the first 6 percent of base compensation that a participant contributes to the Plan. During 2002, fifty percent of the Company matching contribution was invested in the White Mountains Stock Fund and all remaining contributions were invested in the employee directed investment options. Effective January 1, 2003, the company match mirrors the employee directed investment options. Effective January 1, 2003, eligible participants who attain age 50 before the end of the Plan year can make catch up contributions to the Plan. Contributions are subject to IRS limitations.

Employees hired between June 1, 2001 and April 11, 2003 have been and will be provided with the equivalent of two common shares of White Mountains Insurance Group, Ltd. on the first day of the second month of the quarter following one year of service with the Company. In 2003 and 2002, the Company contributed $729,422 and $141,417, respectively, to these employees. Contributions into the White Mountain Stock Fund can be immediately directed by the participant into another investment option.

Participant Accounts

Each participant's account is credited with the participant's contribution and allocations of (a) the Company's contribution (b) Plan earnings, net of an allocation of investment fees and (c) applicable loan fees. Allocations are based on participant earnings or account balances, as defined. The benefit to which a participant is entitled is the benefit that can be provided from the participant's vested account.

Vesting

Participants are vested immediately in their contributions plus actual earnings thereon. Vesting in the Company's contribution portion of their accounts is based on years of continuous service. A participant is 100 percent vested after three years of credited service.

Forfeitures

Forfeitures are used to reduce future Company contributions. The balances as of December 31, 2003 and 2002, in the forfeiture account were $11,952 and $6,727, respectively. During 2003 and 2002, $428,273 and $329,014, respectively, of forfeited funds were used to offset employer contributions.

Participant Loans

Participants may borrow from their fund accounts a minimum of $500 up to a maximum of $50,000 or 50 percent of their vested account balance, whichever is less. The loans are secured by the balance in the participant's account and bear interest at the prime rate (4.00% and 4.25% at December 31, 2003 and December 31, 2002, respectively) plus 1 percent as of the beginning of the month in which the loan was made.

Payment of Benefits

On termination of service due to death, disability, or retirement, a participant may elect to receive either a lump-sum amount equal to the value of the participant's vested interest in his or her account, or annual installments over time. For termination of service for other reasons, a participant may only receive the value of the vested interest in his or her account as a lump-sum distribution.

Expenses

During 2003 and 2002, the Company paid the majority of administrative expenses relating to the Plan except for certain investment management fees paid by the Plan. Effective January 1, 2004, the participants will pay all administrative expenses formerly paid by the Company including independent audit and compliance testing fees.

Plan Termination

While the Company has not expressed any intent to discontinue their contributions or terminate the Plan, they are free to do so at any time. In the event the Plan is terminated, the Plan provides that each participant's balance, inclusive of Company contributions, becomes immediately 100 percent vested and shall be distributed to the participants.

B. Investment Options

During the plan years ended December 31, 2003 and 2002, participants were able to allocate their contributions among various registered investment company options, a company stock fund and four

specific Plan-sponsored funds comprised of stocks, bonds, government securities and guaranteed investment contracts as follows:

Columbia Mid Cap Value Fund (formerly the Liberty Select Value Fund, Class Z)
OneBeacon Equity Fund
OneBeacon Fixed Income Fund
OneBeacon Fully Managed Fund
OneBeacon Insurance Group Stable Value Fund
Vanguard 500 Index Fund
Vanguard Asset Allocation Fund
Vanguard Extended Market Index Fund
Vanguard High-Yield Corporate Fund
Vanguard International Growth Fund
Vanguard Long-Term Corporate Fund
Vanguard Morgan Growth Fund
Vanguard Prime Money Market Fund
Vanguard Short-Term Corporate Fund
Vanguard Small-Cap Index Fund
Vanguard Total International Stock Index Funds
Vanguard U.S. Growth Fund
Vanguard Wellington Fund
Vanguard Windsor Fund
Vanguard Windsor II Fund
White Mountains Stock Fund

C. Summary of Accounting Policies

The following accounting policies, which conform to accounting principles generally accepted in the United States of America, have been used consistently in the preparation of the Plan's financial statements:

Basis of Accounting

The financial statements of the Plan are prepared under the accrual method of accounting.

Use of Estimates

The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of additions and deductions during the reporting period. Actual results could differ from those estimates.

Investment Valuation and Income Recognition

The Plan's investments are stated at fair value, except for its investment contract(s), which are valued at contract value which approximates fair value (Note E). Shares of company stock, common stock, preferred stock, U.S. government securities, corporate bonds, and registered investment

companies are valued at quoted market prices, which represent the net asset value of shares held by the Plan at year-end. Participant loans are valued at cost, which approximates fair value. Shares in common/collective trust funds are valued at the net asset value of the Plan's shares held, as determined by the Custodian. Purchases and sales of investments are recorded on a trade-date basis. Interest income is accrued when earned. Dividend income is recorded on the ex-dividend date. Capital gain distributions are included in dividend income.

In accordance with the policy of stating investments at fair value, the Plan presents in the Statements of Changes in Net Assets Available for Benefits the net appreciation (depreciation) in the fair value of its investments which consists of the realized gains or losses and the unrealized appreciation (depreciation) on those investments.

Benefit Payments

Benefits are recorded when paid.

Risks and Uncertainties

The Plan provides various investment options in any combination of stocks, bonds, fixed income securities, registered investment companies, money market funds, and other investment securities. Investment securities are exposed to various risks such as interest rate, market, and credit risks. Due to the level of risk associated with certain investment securities, and a level of uncertainty related to changes in the value of investment securities, it is at least reasonably possible that changes in risks in the near term would materially affect participants' account balances and the amounts reported in the Statements of Net Assets Available for Benefits and the Statements of Changes in Net Assets Available for Benefits.

Reclassifications

Certain reclassifications were made to the prior year financial statements to conform to current year presentation.

D. Investments

The following presents the fair value of investments that represent 5 percent or more of the Plan's net assets.

		As of December 31,
		2003		2002
Investments, at fair value
	Vanguard 500 Index Fund	$	31,451,292	$	25,176,783
	Vanguard Prime Money Market Fund		N/A		17,590,921
	Vanguard Wellington Fund		22,981,133		19,927,651
	Vanguard Windsor Fund		32,472,877		26,217,886

During 2003 and 2002, the Plan's investments (including gains and losses on investments bought and sold, as well as held during the year) appreciated/(depreciated) in value as follows:

		Years Ended December 31,
		2003		2002
Net appreciation/(depreciation) in fair value of investments, by type
	Common Stock	$	18,404,021	$	(6,107,081	)
	Preferred Stock		1,012,648		180,463
	White Mountains Stock		2,940,579		(346,363	)
	Corporate Bonds		1,702,208		3,155,336
	US Government Bonds		19,118		270,652
	Registered Investment Companies		32,240,667		(28,386,685	)

	Net appreciation/(depreciation) in fair value of investments	$	56,319,241	$	(31,233,678	)

E. Investment Contracts (OneBeacon Insurance Stable Value Fund)

The Plan has entered into benefit-responsive investment contracts with Bank of America, CDC Capital, GE Life and Annuity Insurance, John Hancock Mutual, JP Morgan Chase Bank, Metropolitan Life Insurance, New York Life Insurance, Rabobank Nederland, State Street Bank, Travelers, and Vanguard Prime Money Market Fund. The contract is credited with earnings on the underlying investments and charged for participant withdrawals and administrative expenses. The contracts are included in the financial statements at contract value, which approximates fair value, as reported to the Plan by these institutions. Contract value represents contributions made under the contracts, plus earnings, less participant withdrawals and administrative expenses. The average yields during the years ended December 31, 2003 and 2002 were 4.86 percent and 5.29 percent, respectively. The crediting interest rates ranged from 3.55 to 7.64 percent and 3.85 to 7.64 percent at December 31, 2003 and 2002, respectively. The crediting interest rate is based on a formula agreed upon with the issuer, but may not be less than 0 percent. Such interest rates on synthetic contracts are reviewed on a quarterly basis for resetting.

F. Related Party Transactions

The Plan invests in shares of mutual funds managed by an affiliate of Vanguard Fiduciary Trust Company ("VFTC"). VFTC acts as trustee for only those investments as defined by the Plan. The Plan also has investments, which are managed by White Mountain Advisors, an affiliate of the Company. Transactions in such investments qualify as party-in-interest transactions, which are exempt from the prohibited transaction rules. Participants' loans also constitute party-in-interest transactions.

The Plan invests in the White Mountains Stock Fund (the "Fund") which is comprised of common shares of White Mountains Insurance Group, Ltd. (the Parent Company) and small amounts of cash invested in the Vanguard Prime Money Market Fund. The share values of the Fund are recorded and maintained by VFTC, Trustee of the Plan. During the years ended December 31, 2003 and 2002, the Plan purchased shares in the Fund in the amounts of $2,929,945 and $5,021,187, respectively; sold shares in the Fund of $2,019,919 and $2,652,396, respectively; and had net appreciation (depreciation) in the Fund of $2,940,579 and $(346,363), respectively. The total value of the Plan's investment in the Fund was $10,596,218 and $6,745,613 at December 31, 2003 and 2002, respectively.

G. Tax Status

The Internal Revenue Service has determined and informed the Company by a letter dated January 16, 2002, that the Plan and related trust are designed in accordance with applicable sections of the Internal Revenue Code ("IRC"). Management believes the Plan is designed and operates in accordance with the IRC, therefore, no provision for income taxes is required.

H. 2002 Transfer Out

Effective December 31, 2001, approximately 1,972 full time employees of the property and casualty business were transferred to Liberty Mutual. Employees with loan balances could either pay off their loan and remain in the Plan or transfer their loan and investments in their entirety to the Liberty Mutual Thrift Incentive Plan. In January 2002, $17,242,618 in loans and investments were transferred out of the Plan.

OneBeacon Insurance Savings Plan

Schedule of Assets (Held at End of Year)
(Form 5500, Schedule H, Part IV, Line 4i)

Identity of Issue		Security Description	Current Value
Cash and cash equivalents
	*TBC INC POOLED EMPLOYEE FUNDS	3,562,699 units	$	3,562,699

				3,562,699

Common Stock
	ABITIBI CONSOLIDATED INC	30,000 shares		243,300
	ALEXANDER & BALDWIN INC	1,500 shares		50,535
	AMERADA HESS CORP	100,000 shares		5,317,000
	AON CORP COM	55,000 shares		1,316,700
	ARCHER DANIELS MIDLAND CO	90,000 shares		1,369,800
	AUTOMATIC DATA PROCESSING INC	25,000 shares		990,250
	BERKSHIRE HATHAWAY INC DEL CLASS B	550 shares		1,548,250
	CALLAWAY GOLF CO	15,000 shares		252,750
	CAPITOL FED FINL	30,000 shares		1,081,800
	CHARTER FINL CORP WEST PT GA	25,000 shares		931,750
	DIAMOND OFFSHORE DRILLING INC	20,000 shares		410,200
	EASTMAN CHEM CO	30,000 shares		1,185,900
	EL PASO ELEC CO	260,000 shares		3,471,000
	FAIRMONT HOTELS & RESORTS INC	65,000 shares		1,764,100
	FIRSTENERGY CORP	115,000 shares		4,048,000
	FORTUNE BRANDS INC	4,000 shares		285,960
	GREAT LAKES CHEM CORP	150,000 shares		4,078,500
	HASBRO INC	4,000 shares		85,120
	IDACORP INC	5,000 shares		149,600
	IMPERIAL CHEMICAL INDUSTRIES	100,000 shares		356,240
	LONGVIEW FIBRE CO	65,000 shares		802,750
	MARATHON OIL CORP	150,000 shares		4,963,500
	MCDONALDS CORP	47,000 shares		1,167,010
	MEREDITH CORP	55,000 shares		2,684,550
	NUI CORP	27,000 shares		435,240
	OCTEL CORP	80,000 shares		1,575,200
	OVERSEAS SHIPHOLDING GROUP	25,000 shares		851,250
	PEOPLES BANK	42,000 shares		1,369,200
	POTLATCH CORP	45,000 shares		1,564,650
	RYDER SYS INC	70,000 shares		2,390,500
	TECK COMINCO LTD CL B SUB VTG	80,000 shares		1,357,632
	UNISOURCE ENERGY CORP	250,000 shares		6,165,000
	UNOCAL CORP	85,000 shares		3,130,550
	XCEL ENERGY INC	47,000 shares		798,060

				58,191,847
Preferred Stock
	CMS ENERGY CORP PFD CONV 144A	15,000 shares		838,125
	ROUSE CO EXCH CVT PFD SER B	18,000 shares		1,116,000

	UNOCAL CAP TR EXCH CVT PFD	95,000 shares	$	5,130,000

				7,084,125

Company Stock
*WHITE MOUNTAINS STOCK		22,949 shares		10,555,393

				10,555,393

Corporate Bonds
	3M EMPLOYEE STK OWNERSHIP 144A	5.620% 07/15/2009 $617,365 par		667,335
	AMERICAN GEN FIN MTN #TR00378	5.375% 10/01/2012 $2,000,000 par		2,062,362
	AON CORP SR DEB CVT	3.500% 11/15/2012 $500,000 par		617,500
	CONOCO INC SR NTS	6.350% 04/15/2009 $2,000,000 par		2,243,670
	COORS BREWING CO	6.375% 05/15/2012 $2,000,000 par		2,178,718
	DEERE & CO DEB	7.850% 05/15/2010 $2,000,000 par		2,416,662
	DOVER CORP NT	6.450% 11/15/2005 $1,000,000 par		1,078,977
	DU PONT EI DE NEMOURS & CO NT	6.875% 10/15/2009 $2,000,000 par		2,313,318
	ENERGY EAST CORP NT	5.750% 11/15/2006 $2,500,000 par		2,699,360
	FOSTERS FIN CORP NT 144A	6.875% 06/15/2011 $1,000,000 par		1,137,333
	HARTFORD LIFE INC SR NT	7.375% 03/01/2031 $1,000,000 par		1,172,483
	HARVARD UNIV MASS	8.125% 04/15/2007 $1,045,000 par		1,214,342
	INCO LTD CONV DEB	1.000% 03/14/2023 $500,000 par		694,375
	INTERNATIONAL PAPER CO	7.500% 05/15/2004 $1,000,000 par		1,019,971
	KERR MCGEE CORP SUB DEB CVT	5.250% 02/15/2010 $1,500,000 par		1,580,625
	KINDER MORGAN ENERGY SR NT	7.500% 11/01/2010 $1,000,000 par		1,171,574
	LOEWS CORP SUB NOTES CVT	3.125% 09/15/2007 $1,250,000 par		1,207,813
	OHIO CAS CORP NT CVT	5.000% 03/19/2022 $500,000 par		526,250

	PEARSON INC GTD NT 144A			7.375% 09/15/2006 $1,000,000 par	$	1,113,220
	SARA LEE CORP MTN # TR 00020			6.275% 02/23/2004 $1,500,000 par		1,508,102
	SIERRA PAC RES NEW NT CONV			7.250% 02/14/2010 $500,000 par		943,750
	ST PAUL COS INC MTN # TR 00054			6.730% 07/14/2005 $1,000,000 par		1,065,519
	TECK COMINCO LTD CV SUB DEB			3.750% 07/15/2006 $1,000,000 par		960,000
	TEXTRON FINL CORP MTN #TR00622			2.750% 06/01/2006 $2,000,000 par		1,995,870
	TRIBUNE CO MTN #TR 00043			5.900% 01/24/2006 $1,000,000 par		1,059,266
	TRIZEC HAHN CORP DEBS EXCH			3.000% 01/29/2021 $5,000,000 par		3,893,750
	USF&G CORP SUB CVT NT			ZERO CPN 03/03/2009 $1,500,000 par		1,194,375
	WELLPOINT HEALTH NETWORKS NT			6.375% 06/15/2006 $1,000,000 par		1,090,942

						40,827,462

US Government Securities
	FEDERAL HOME LN MTG CORP DEBS			7.800% 09/12/2016 $1,000,000 par		1,136,409
	US TREASURY NOTES			3.000% 02/15/2008 $5,000,000 par		5,023,240

						6,159,649

OneBeacon Insurance Group Stable Value Fund—Insurance and Investment Contracts
	BANK OF AMERICA 03-010 WRAPPER CONTRACT			3.68% 06/30/2008		5,430
		UNDERLYING ASSETS
			*VANGUARD TARGETED RETURN TRUST (4-07)	12/31/2007		2,057,712
			*VANGUARD TARGETED RETURN TRUST (2-08)	06/30/2008		1,013,279

			TOTAL CONTRACT VALUE			3,076,421

	CDC CAPITAL 362-03 WRAPPER CONTRACT			5.75% 02/28/2004		(2,516,098	)
		UNDERLYING ASSETS
			MORGAN STANLEY CAP 98-HF2 A1			1,302,346
			NATIONSLINK FUNDING CORP 99-SL A6			2,330,865
			PROVIDENT BANK HOME EQUITY LN TR 1998-2 A5			901,971

			TOTAL CONTRACT VALUE			2,019,084

	CDC FINANCIAL PRODUCTS 1362-01 WRAPPER CONTRACT			3.55% constant duration	$	(14,140	)
		UNDERLYING ASSETS
			*VFTC INTERMEDIATE-TERM TRUST			5,701,883

			TOTAL CONTRACT VALUE			5,687,743

	GE LIFE AND ANNUITY GS-3328			6.77% 5/15/2004		1,335,501

	JOHN HANCOCK MUTUAL GAC-14647			6.77% 7/15/2004		2,671,003

	JP MORGAN CHASE BANK JPMBEAC01 WRAPPER CONTRACT			4.30% constant duration		(164,543	)
		UNDERLYING ASSETS
			*VFTC MORTGAGE BACKED SECURITIES TRUST			3,385,821
			*VANGUARD TOTAL BOND MARKET INDEX FUND			4,658,003

			TOTAL CONTRACT VALUE			7,879,281

	METROPOLITAN LIFE 25656			7.13% 05/15/2005		5,006,065

	METROPOLITAN LIFE 25855			5.93% 07/15/2005		2,344,526

	NEW YORK LIFE GA31132			7.64% 10/15/2004		5,185,064

	NEW YORK LIFE GA31132-002			6.29% 08/15/2005		4,805,675

	RABOBANK NEDERLAND GAC 099601 WRAPPER CONTRACT			4.27% constant duration		(362,714	)
		UNDERLYING ASSETS
			*VFTC INTERMEDIATE-TERM TRUST			15,411,593

			TOTAL CONTRACT VALUE			15,048,879

	RABOBANK NEDERLAND GAC 069701 WRAPPER CONTRACT			4.53% constant duration		(229,250	)
		UNDERLYING ASSETS
			*VANGUARD TOTAL BOND MARKET INDEX FUND			4,640,372

TOTAL CONTRACT VALUE						4,411,122

	STATE STREET BANK 101049 WRAPPER CONTRACT			4.20% 09/30/2007	$	(319,173	)
		UNDERLYING ASSETS
			*VANGUARD TARGETED RETURN TRUST (4-05)	12/31/2005		2,425,508
			*VANGUARD TARGETED RETURN TRUST (1-06)	03/31/2006		1,805,882
			*VANGUARD TARGETED RETURN TRUST (2-06)	06/30/2006		1,798,149
			*VANGUARD TARGETED RETURN TRUST (3-06)	09/30/2006		1,585,027
			*VANGUARD TARGETED RETURN TRUST (4-06)	12/31/2006		1,598,632
			*VANGUARD TARGETED RETURN TRUST (1-07)	03/31/2007		1,600,570
			*VANGUARD TARGETED RETURN TRUST (2-07)	06/30/2007		1,604,848
			*VANGUARD TARGETED RETURN TRUST (3-07)	09/30/2007		1,609,673

			TOTAL CONTRACT VALUE			13,709,116

	TRAVELERS GR-18716			3.99% 12/05/2008		4,012,023

	*VANGUARD PRIME MONEY MARKET FUND			0.77% constant duration		1,166,888

						78,358,391

Participant Loans
	*PARTICIPANT LOANS			5.0% — 5.25%		4,884,748

						4,884,748

Registered Investment Companies
	COLUMBIA MID CAP VALUE FUND			359,490 units		8,688,873
	*VANGUARD 500 INDEX FUND			306,334 units		31,451,292
	*VANGUARD ASSET ALLOCATION FUND			355,395 units		8,017,713
	*VANGUARD EXTENDED MARKET INDEX FUND			417,060 units		11,118,825
	*VANGUARD HIGH-YIELD CORP FUND			255,807 units		1,632,046
	*VANGUARD INT'L GROWTH FUND			425,776 units		6,867,764
	*VANGUARD LT CORPORATE FUND			1,054,115 units		9,771,645
	*VANGUARD MORGAN GROWTH FUND			64,372 units		957,205
	*VANGUARD PRIME MONEY MARKET FUND			15,694,284 units		15,694,284
	*VANGUARD SMALL-CAP INDEX FUND			313,204 units		7,078,413
	*VANGUARD ST CORPORATE FUND			334,647 units		3,614,185
	*VANGUARD TOTAL INT'L STOCK INDEX FUND			195,893 units		2,084,302
	*VANGUARD U.S. GROWTH FUND			69,839 units		1,058,756
	*VANGUARD WELLINGTON FUND			797,679 units		22,981,133
	*VANGUARD WINDSOR FUND			1,997,102 units		32,472,877
	*VANGUARD WINSOR II FUND			433,643 units		11,487,210

						174,976,523

					$	384,600,837

*: Denotes party-in-interest.

Cost omitted for participant directed investments.

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Exhibit 99(a)

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Exhibit 99(b)

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (No. 333-68438) of OneBeacon Insurance of our report dated June 16, 2004 relating to the financial statements of the OneBeacon Insurance Savings Plan, which appears in this Form 11-K.

/s/ PricewaterhouseCoopers LLP

Boston, Massachusetts
June 28, 2004

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Exhibit 99(b)