A.M. Best has assigned a Financial Strength Rating of A (Excellent) and a Long-Term Issuer Credit Rating of “a” to OBI America Insurance Company (OBIA) (Harrisburg, PA). The outlook assigned to these Credit Ratings (ratings) is stable.

The ratings recognize the 100% reinsurance agreement between OBIA and its affiliate, Atlantic Specialty Insurance Company. Both companies are rating unit members of OneBeacon Insurance Group (OneBeacon) and subsidiaries of OneBeacon Insurance Group, Ltd. [NYSE: OB]. OneBeacon’s ultimate parent is White Mountains Insurance Group, Ltd. [NYSE: WTM].

OneBeacon is a specialty property/casualty insurance group targeting specialized insurance products, industries, classes of business and risk characteristics. OBIA was formed to expand OneBeacon’s existing platform for writing workers’ compensation coverage.

While OBIA’s ratings are stable, future positive rating actions may result if the group’s underwriting and operating results outperform its peers for an extended period of time. Negative rating actions may result if the group’s underwriting and operating performance falls markedly short of A.M. Best’s expectation or if there is a material weakening of risk-adjusted capitalization.

This press release relates to Credit Ratings that have been published on A.M. Best’s website. For all rating information relating to the release and pertinent disclosures, including details of the office responsible for issuing each of the individual ratings referenced in this release, please see A.M. Best’s Recent Rating Activity web page. For additional information regarding the use and limitations of Credit Rating opinions, please view Understanding Best’s Credit Ratings.

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