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Third-Party Reinsurance (Tables) | 12 Months Ended
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Dec. 31, 2011
Third-Party Reinsurance |
Schedule of direct assumed and ceded amounts |
The effects of reinsurance on White Mountains’ insurance and reinsurance subsidiaries’ written and earned premiums and on losses and LAE were as follows:
|  | Year ended December 31, 2011 |
Millions |  | OneBeacon |  | Sirius Group |  | Other Operations |  | Total |
Written premiums: |  |  |  |  |  |  |  |  |
Direct |  | $ | 1,077.6 |  | $ | 139.5 |  | $ | — |  | $ | 1,217.1 |
Assumed |  | 48.2 |  | 988.6 |  | — |  | 1,036.8 |
Gross written premiums |  | 1,125.8 |  | 1,128.1 |  | — |  | 2,253.9 |
Ceded |  | (62.9 | ) | (212.4 | ) | — |  | (275.3 | )
Net written premiums |  | $ | 1,062.9 |  | $ | 915.7 |  | $ | — |  | $ | 1,978.6 |
Earned premiums: |  |  |  |  |  |  |  |  |
Direct |  | $ | 1,138.5 |  | $ | 128.5 |  | $ | — |  | $ | 1,267.0 |
Assumed |  | 43.1 |  | 989.8 |  | — |  | 1,032.9 |
Gross earned premiums |  | 1,181.6 |  | 1,118.3 |  | — |  | 2,299.9 |
Ceded |  | (166.1 | ) | (206.0 | ) | — |  | (372.1 | )
Net earned premiums |  | $ | 1, 015.5 |  | $ | 912.3 |  | $ | — |  | $ | 1,927.8 |
Losses and LAE: |  |  |  |  |  |  |  |  |
Direct |  | $ | 1,151.1 |  | $ | 80.0 |  | $ | — |  | $ | 1,231.1 |
Assumed |  | 36.1 |  | 627.8 |  | — |  | 663.9 |
Gross losses and LAE |  | 1,187.2 |  | 707.8 |  | — |  | 1,895.0 |
Ceded |  | (606.3 | ) | (81.8 | ) | — |  | (688.1 | )
Net losses and LAE |  | $ | 580.9 |  | $ | 626.0 |  | $ | — |  | $ | 1,206.9 |
|  | Year ended December 31, 2010 |
Millions |  | OneBeacon |  | Sirius Group |  | Other Operations |  | Total |
Written premiums: |  |  |  |  |  |  |  |  |
Direct |  | $ | 1,501.5 |  | $ | 121.6 |  | $ | — |  | $ | 1,623.1 |
Assumed |  | 57.7 |  | 957.5 |  | — |  | 1,015.2 |
Gross written premiums |  | 1,559.2 |  | 1,079.1 |  | — |  | 2,638.3 |
Ceded (1) |  | (400.2 | ) | (213.3 | ) | — |  | (613.5 | )
Net written premiums |  | $ | 1,159.0 |  | $ | 865.8 |  | $ | — |  | $ | 2,024.8 |
Earned premiums: |  |  |  |  |  |  |  |  |
Direct |  | $ | 1,648.7 |  | $ | 117.9 |  | $ | — |  | $ | 1,766.6 |
Assumed |  | 64.2 |  | 929.7 |  | — |  | 993.9 |
Gross earned premiums |  | 1,712.9 |  | 1,047.6 |  | — |  | 2,760.5 |
Ceded (1) |  | (309.0 | ) | (199.7 | ) | — |  | (508.7 | )
Net earned premiums |  | $ | 1,403.9 |  | $ | 847.9 |  | $ | — |  | $ | 2,251.8 |
Losses and LAE: |  |  |  |  |  |  |  |  |
Direct |  | $ | 877.1 |  | $ | 59.4 |  | $ | — |  | $ | 936.5 |
Assumed |  | 138.4 |  | 684.4 |  | — |  | 822.8 |
Gross losses and LAE |  | 1,015.5 |  | 743.8 |  | — |  | 1,759.3 |
Ceded (1) |  | (157.3 | ) | (212.8 | ) | — |  | (370.1 | )
Net losses and LAE |  | $ | 858.2 |  | $ | 531.0 |  | $ | — |  | $ | 1,389.2 |
(1) | During 2010, OneBeacon ceded written premiums of $262.2, earned premiums of $165.0 and loss and LAE of $86.5 pursuant to the Commercial Lines Transaction.
Listing of OneBeacon's top reinsurers |
The following table provides a listing of OneBeacon’s top reinsurers, excluding industry pools and associations and affiliates of White Mountains, based upon recoverable amounts, the percentage of total reinsurance recoverables and the reinsurer’s A.M. Best rating.
Top Reinsurers ($ in millions) |  | Balance at December 31, 2011 |  | % of Total |  | A.M. Best Rating(1) |
National Indemnity Company and General Reinsurance Corporation (2) |  | $ | 1,540.6 |  | 66 | % |  | A++ |
Hanover Insurance Group Ltd. |  | 90.9 |  | 4 | % |  | A |
Tokio Marine and Nichido Fire (3) |  | 57.1 |  | 2 | % |  | A++ |
Tower Group Inc. |  | 35.1 |  | 1 | % |  | A- |
Munich Reinsurance America |  | 26.4 |  | 1 | % |  | 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 “A-” (Excellent, which is the fourth highest of fifteen financial strength ratings). Ratings are as of December 31, 2011.
(2) | Includes $198.3 of Third-Party Recoverables, which NICO would pay under the terms of the NICO Cover if they are unable to collect from third-party reinsurers.
(3) | Includes $30.5 of reinsurance recoverables from various third-party reinsurers that are guaranteed by Tokio Marine and Nichido Fire under the terms of a 100% quota share reinsurance agreement between Houston General Insurance Company and Tokio Marine and Nichido Fire.
Listing of Sirius's top reinsurers |
The following table provides a listing of Sirius Group’s top reinsurers based upon recoverable amounts, the percentage of total recoverables and the reinsurer’s A.M. Best Rating.
Top Reinsurers ($ in millions) |  | Balance at December 31, 2011 |  | % of Total |  | A.M. Best Rating(1) |  | % Collateralized |
General Reinsurance Corporation |  | $ | 42.7 |  | 12 | % |  | A++ |  | 1 | %
Swiss Re Group |  | 40.2 |  | 11 | % |  | A+ |  | 20 | %
Olympus (2) |  | 35.5 |  | 10 | % |  | NR-5 |  | 100 | %
Lloyds of London(3) |  | 27.2 |  | 8 | % |  | A |  | 8 | %
Michigan Catastrophic Claims Association |  | 14.6 |  | 4 | % |  | N/A(4) |  | — | %
(1) | A.M. Best ratings as detailed above are: “NR-5” (Not formally followed), “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).
(2) | Non-U.S. insurance entities. Balances are fully collateralized through funds held, letters of credit or trust agreements.
(3) | Represents the total of reinsurance recoverables due to Sirius Group from all Lloyds Syndicates.
(4) | Michigan Catastrophic Claims Association (“MCCA”) is a non-profit unincorporated association of 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 as a result of its acquisition of Stockbridge Insurance Company.

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- Definition Tabular disclosure of the top five reinsurers that have assumed business from OneBeacon (excluding industry pools and associations) based on the amount recoverable from each reinsurer. The disclosure for each reinsurer also includes the amount recoverable as a percentage of OneBeacon's consolidated reinsurance recoverables and the A.M Best Company, Inc. ("A.M. Best") rating. + References No definition available. + Details
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- Definition Tabular disclosure of the top five reinsurers that have assumed business from Sirius based on the amount recoverable from each reinsurer. The disclosure for each reinsurer also includes the amount recoverable as a percentage of Sirius's total reinsurance recoverables, the A.M Best Company, Inc. ("A.M. Best") rating and the percentage of the amount recoverable that is collateralized. + References No definition available. + Details
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