A.M. Best Places Rock River Under Review

Business Wire, Sept 27, 2001

Business Editors

OLDWICK, N.J.--(BUSINESS WIRE)--Sept. 27, 2001

A.M. Best Co. has placed the financial strength rating of A (Superior) for Rock River Insurance Company, Moline, Ill., under review with negative implications.

This rating action follows the signing of a definitive agreement for Arch Capital Group Ltd. (NADAQ: ACGL) to acquire Rock River. Rock River is a fully reinsured subsidiary of and derives its rating from Sentry Insurance a Mutual Company with an A.M. Best financial strength rating of A (Superior). According to the agreement Rock River will now be owned by First American Insurance Company, which currently has an A.M. Best financial strength rating of A- (Excellent). First American is a member of the Arch Capital Group of companies and is an admitted company with licenses in 49 states. This transaction is expected to close during the fourth quarter of 2001. The rating of Rock River will remain under review pending regulatory approval and further discussions with management regarding the strategic fit of Rock River in the Arch Capital Group of companies.

Rock River is an approved excess and surplus lines insurer in 45 states and the District of Columbia as well as an admitted insurer in two other states. Under the terms of the agreement, existing policies and other liabilities of Rock River will continue to be reinsured by Sentry Insurance a Mutual Company.

Arch Capital Group Ltd. is a Bermuda based, diversified financial services company with over $500 million in assets. The Arch Group is engaged in a range of insurance and financial services activities through subsidiaries comprising its Arch Services division and the ownership of intermediaries, underwriting agencies, service providers and insurance companies.

A.M. Best Co., established in 1899, is the world's oldest and most authoritative insurance rating and information source. For more information, visit A.M. Best's Web site at www.ambest.com.