OneBeacon Files Shelf Registration Statement to Replace Expiring Registration Statement

HAMILTON, Bermuda, June 13, 2011 /PRNewswire/ -- OneBeacon Insurance Group, Ltd. (NYSE: OB) announced today that it has filed a shelf registration statement on Form S-3 with the Securities and Exchange Commission (SEC) to replace its registration statement on Form S-3 (File No. 333-152078), filed on July 2, 2008, which is expiring pursuant to the rules of the Securities Act of 1933, as amended. When declared effective by the SEC, the registration statement will permit the company and certain of its subsidiaries, from time to time, to offer and sell up to $1 billion of common shares, preferred shares, depositary shares, debt securities and other specified securities. The terms of any offering by the company under the registration statement will be established at the time of the offering and will be described in a prospectus supplement. The registration statement is intended to provide the company with additional flexibility to access capital markets for general corporate purposes, subject to market conditions and the company's capital needs. OneBeacon has no intention to offer or sell any of its OneBeacon Class A common shares at this time.

In addition, the registration statement will permit the resale of up to 71,754,738 OneBeacon Class B common shares owned by certain subsidiaries of White Mountains Insurance Group, Ltd. (collectively, "White Mountains"). The Class B common shares would automatically convert into OneBeacon Class A common shares upon resale. OneBeacon would not receive any of the proceeds from the sale of any Class B common shares by White Mountains. White Mountains has informed OneBeacon that it has no intention to offer or sell any such common shares at this time.

The registration statement has been filed with the SEC, but has not yet become effective. Any offers, solicitations of offers to buy, or sales of these securities will only be made once the shelf registration statement has been declared effective by the SEC, including any prospectuses and prospectus supplements. These securities may not be sold, nor may offers to buy be accepted prior to the time that the registration statement becomes effective. This news release shall not constitute an offer to sell, or the solicitation of an offer to buy, nor shall there be any sale of these securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state.

About OneBeacon: OneBeacon Insurance Group, Ltd. is a Bermuda-domiciled holding company that is publicly traded on the New York Stock Exchange under the symbol "OB." OneBeacon's underwriting companies offer a range of specialty insurance products sold through independent agencies, regional and national brokers, wholesalers and managing general agencies. The company's businesses include OneBeacon Professional Insurance, International Marine Underwriters, OneBeacon Accident Group, OneBeacon Entertainment, OneBeacon Energy Group, OneBeacon Government Risks, A.W.G. Dewar (tuition refund), collector cars and boats written through Hagerty Insurance Agency, OneBeacon Technology Insurance, OneBeacon Specialty Property, OneBeacon Property and Inland Marine, and OneBeacon Excess and Surplus Lines. The company also offers products and services to assigned risk markets through its AutoOne division. OneBeacon's insurance businesses are national in scope.

Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995

This press release may contain "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. All statements, other than statements of historical facts, included or referenced in this release which address activities, events or developments which we expect or anticipate will or may occur in the future are forward-looking statements. The words "will," "believe," "intend," "expect," "anticipate," "project," "estimate," "predict" and similar expressions are also intended to identify forward-looking statements. These forward-looking statements include, among others, statements with respect to OneBeacon's:

• change in book value per share or return on equity;
• business strategy;
• financial and operating targets or plans;
• incurred loss and loss adjustment expenses and the adequacy of its loss and loss adjustment expense reserves and related reinsurance;
• projections of revenues, income (or loss), earnings (or loss) per share, dividends, market share or other financial forecasts;
• expansion and growth of our business and operations; and
• future capital expenditures.

These statements are based on certain assumptions and analyses made by OneBeacon in light of its experience and perception of historical trends, current conditions and expected future developments, as well as other factors believed to be appropriate in the circumstances. However, whether actual results and developments will conform to our expectations and predictions is subject to a number of risks and uncertainties that could cause actual results to differ materially from expectations, including:

• claims arising from catastrophic events, such as hurricanes, windstorms, earthquakes, floods, fires, explosions, terrorist attacks or severe winter weather;
• recorded loss and loss adjustment expense reserves subsequently proving to have been inadequate;
• the continued availability and cost of reinsurance coverage;
• the continued availability of capital and financing;
• general economic, market or business conditions;
• business opportunities (or lack thereof) that may be presented to it and pursued;
• competitive forces, including the conduct of other property and casualty insurers and agents;
• changes in domestic or foreign laws or regulations, or their interpretation, applicable to OneBeacon, its competitors, its agents or its customers;
• an economic downturn or other economic conditions adversely affecting its financial position including stock market volatility;
• actions taken by ratings agencies from time to time, such as financial strength or credit ratings downgrades or placing ratings on negative watch;
• the risks that are described from time to time in OneBeacon's filings with the Securities and Exchange Commission, including but not limited to OneBeacon's Annual Report on the Form 10-K for the fiscal year ended December 31, 2010 filed February 28, 2011.

Consequently, all of the forward-looking statements made in this press release are qualified by these cautionary statements, and there can be no assurance that the actual results or developments anticipated by OneBeacon will be realized or, even if substantially realized, that they will have the expected consequences to, or effects on, OneBeacon or its business or operations. OneBeacon assumes no obligation to update publicly any such forward-looking statements, whether as a result of new information, future events or otherwise.

Web site:   www.onebeacon.com

SOURCE OneBeacon Insurance Group, Ltd.