Third Party Reinsurance (Tables)

9 Months Ended

Sep. 30, 2012

The following table provides a listing of OneBeacon’s top reinsurers, based upon recoverable amounts, the percentage of total paid and unpaid reinsurance recoverables and the reinsurer’s A.M Best Company, Inc. (“A.M. Best”) rating.



Top Reinsurers (Millions)	Balance at September 30, 2012		% of Total		A.M. Best Rating ⁽¹⁾
Hannover Ruckversich	$	6.4	15	%	A+
Hartford Steam Boiler	4.6		11	%	A++
Munich Reinsurance America	4.5		10	%	A+
Platinum Underwriters Re	4.1		9	%	A
Transatlantic Reinsurance	2.0		5	%	A

¹⁾A.M. Best ratings as detailed above are: “A++” (Superior, which is the highest of fifteen financial strength ratings), “A+” (Superior, which is the second highest of fifteen financial strength ratings) and “A” (Excellent, which is the third highest of fifteen financial strength ratings).

Listing of Sirius's top reinsurers

The following table provides a listing of Sirius Group’s top reinsurers based upon recoverable amounts, the percentage of total paid and unpaid reinsurance recoverables and the reinsurers’ A.M. Best ratings.



Top Reinsurers (Millions)	Balance at September 30, 2012		% of Total		A.M. Best Rating ⁽¹⁾	% Collateralized
General Reinsurance Corporation	$	42.3	13	%	A++	1	%
Swiss Re Group	33.7		10	%	A+	5	%
Lloyds of London ⁽²⁾	29.9		9	%	A	4	%
Olympus⁽³⁾	28.8		9	%	NR-5	100	%
Michigan Catastrophic Claims Association ⁽⁴⁾	14.6		4	%	N/A	—	%

⁽¹⁾A.M. Best ratings as detailed above are: “A++” (Superior, which is the highest of fifteen financial strength ratings), “A+” (Superior, which is the second highest of fifteen financial strength ratings), “A” (Excellent, which is the third highest of fifteen financial strength ratings) and “NR-5” (Not formally followed).

⁽²⁾Represents the total of reinsurance recoverables due to Sirius Group from all Lloyds Syndicates.

⁽³⁾Non-U.S. insurance entity. The balance is fully collateralized through funds held, letters of credit or trust agreements.

⁽⁴⁾ Michigan Catastrophic Claims Association ("MCCA") is a non-profit unincorporated association., established by the State of Michigan with the power to issue and collect assessments, to which every insurance company that sells automobile coverage in Michigan is required to be a member. A.M. Best does not rate MCCA. Sirius Group acquired its recoverable from MCCA in the acquisition of Stockbridge Insurance Company. As part of the acquisition, Sirius Group obtained $25.0 of reinsurance protection from the seller (currently rated A+ by A.M. Best) for unfavorable loss reserve development, including uncollectible reinsurance.