Heritage

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Commitment to value creation and strong partnership

White Mountains (NYSE: WTM) is a diversified insurance and related financial services holding company that owns and manages businesses seeking a stable, sophisticated partner to drive value creation. Grounded in the core principles of our visionary founder Jack Byrne, we have been careful, opportunistic and successful stewards of our shareholders’ capital for nearly four decades.

We are most proud and protective of our reputation as a good partner – to our shareholders, to other stakeholders in our businesses and to the talented management teams who run them. In the end, doing right by your partners is what guarantees the next deal and the deal after that.

Our enduring principles

Underwriting Comes First
Underwriting Comes First
An insurance enterprise must respect the fundamentals of insurance. There must be a realistic expectation of underwriting profit on all business written, and demonstrated fulfillment of that expectation over time, with focused attention to the loss ratio and to all the professional insurance disciplines of pricing, underwriting and claims management.
Maintain a Disciplined Balance Sheet
Maintain a Disciplined Balance Sheet
The first concern here is that insurance liabilities must always be fully recognized. Loss reserves and expense reserves must be solid before any other aspect of the business can be solid. Pricing, marketing and underwriting all depend on informed judgment of ultimate loss costs that can be managed effectively only with a disciplined balance sheet.
Invest for Total Return
Invest for Total Return
Historically, the insurance industry has emphasized investment income (interest and dividends) above capital gains. White Mountains invests to maximize total return over time. White Mountains manages its bond portfolios for after-tax total return and also invests prudently in equities.
Think Like Owners
Think Like Owners
Thinking like owners has a value all its own. There are stakeholders in a business enterprise, and doing good work requires more than this quarter’s profit. Thinking like an owner embraces all of that and is the touchstone of a capitalist enterprise.

A history of business building and reinvention


Our story began in the early 1980s when Jack Byrne was recruited by American Express to turn around troubled property and casualty insurer Fireman’s Fund. When Jack took Fireman’s Fund public in 1985, it was the largest IPO in American history, and when the insurer was sold to Allianz six years later, shareholders were rewarded with gains exceeding $1 billion. Throughout our history, we’ve been nimble and opportunistic investors; as Jack often said, “You shoot ducks when ducks are flying.”

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1985

Jack Byrne takes Fireman’s Fund public at $25.75 per share.

1991

Fireman’s Fund is sold to Allianz. The remaining holding company and residual assets form the starting point for the future White Mountains.

1994

White Mountains invests in and sponsors the IPO of financial guarantor Financial Security Assurance (FSA).

1996

White Mountains acquires 50% of Folksamerica Re. The remaining stake is acquired in 1998.

1999

White Mountains redomiciles from Delaware to Bermuda, a leading international insurance center.

2000

Amid the fallout of the dot-com bubble, White Mountains makes its initial investment in direct to consumer online auto insurer Esurance.

FSA is acquired by Belgian-French bank Dexia Credit, Europe’s largest municipal lender.

2001

In a transformational transaction, White Mountains acquires CGU’s U.S. insurance operations (renamed OneBeacon) with significant financing and reinsurance provided by Berkshire Hathaway.

White Mountains sponsors the creation of Montpelier Re, replenishing reinsurance capacity in Bermuda after the terrorist attacks of September 11.

2002

Montpelier Re goes public.

2004

White Mountains acquires Sweden-based global reinsurer Sirius International from ABB and later combines this with Folksamerica Re to create Sirius Group.

White Mountains leads a consortium of private investors in the acquisition of Safeco’s life operations (renamed Symetra).

2006

OneBeacon goes public.

2008

White Mountains acquires its initial stake in personal insurance agency Answer Financial (AFI) as a complement to Esurance. AFI became wholly owned later that year.

2010

Symetra goes public.

2011

White Mountains sells Esurance and Answer Financial to Allstate.

2012

White Mountains sponsors the creation of the U.S.’s first mutually-owned municipal bond guarantor Build America Mutual and its primary reinsurer HG Re Ltd.

2014

White Mountains invests in PassportCard, a managing general agent in the travel insurance industry.

White Mountains acquires MediaAlpha, a leading marketing technology company.

White Mountains acquires Tranzact, a leading provider of end-to-end customer acquisition solutions to the insurance sector.

2016

White Mountains sells Sirius Group to China Minsheng Investment Corp.

Symetra is acquired by Sumitomo Life.

White Mountains sells Tranzact to Clayton, Dubilier & Rice.

2017

OneBeacon is acquired by Intact Financial Corp.

2018

White Mountains acquires NSM, a full-service managing general agent and program administrator for specialty property & casualty insurance.

White Mountains invests in Kudu, a provider of capital solutions and advisory services to boutique asset managers.

2020

MediaAlpha goes public.

2021

White Mountains acquires Ark, a leading specialty P&C insurance and reinsurance platform.

2022

White Mountains sells NSM Insurance Group to Carlyle.

White Mountains invests in WM Outrigger Re, an Ark-sponsored reinsurance sidecar.

2023

White Mountains launches White Mountains Partners, which provides first institutional capital to businesses in the essential services, light industrial, and specialty consumer sectors.

2024

White Mountains acquires Bamboo, a managing general agent focused on the California homeowners insurance market.