A.M. Best has assigned a Financial Strength Rating of A (Excellent) and a Long-Term Issuer Credit Rating of “a” to Split Rock Insurance, Ltd. (Split Rock) (Bermuda). The outlook assigned to these Credit Ratings (ratings) is stable.

Split Rock is a wholly owned subsidiary of OneBeacon Insurance Group, Ltd. (OneBeacon) [NYSE:OB]. Split Rock was established in 2013 to reinsure its affiliate, Atlantic Specialty Insurance Company (ASIC), also a subsidiary of OneBeacon. OneBeacon’s ultimate parent is White Mountains Insurance Group, Ltd. [NYSE:WTM].

The ratings of ASIC have been extended to Split Rock due to the implicit and explicit support it receives as a result of its affiliation with ASIC and OneBeacon. Split Rock is fully integrated into OneBeacon’s operations. A material capital infusion to Split Rock from OneBeacon occurred in 2015, demonstrating OneBeacon’s support as Split Rock assumes, via a quota share, 50% of ASIC’s business. Split Rock also benefits from its supportive stand-alone risk-adjusted capitalization and a track record of positive operating results since inception.

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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