A.M. Best Removes From Under Review and Upgrades Ratings of Aspen Specialty Insurance Company.

OLDWICK, N.J. -- A.M. Best Co. has removed from under review with developing implications and upgraded the financial strength rating (FSR) to A (Excellent) from A- (Excellent) and issuer credit rating (ICR) to "a" from "a-" of Aspen Specialty Insurance Company (ASIC) (Bismarck, ND), a wholly owned subsidiary of its ultimate parent, Aspen Insurance Holdings Limited (AIHL) (NYSE: AHL) (Hamilton, Bermuda). The outlook assigned to both ratings is stable.

These rating actions reflect the implementation of reinsurance support provided by ASIC's Bermuda-based affiliate, Aspen Insurance Limited (AIL) (Hamilton, Bermuda), which includes a substantial quota share of all ASIC's net business and a guarantee of all third-party reinsurance recoverables. The quota share reinsurance support for ASIC's business, effective April 1, 2009, represents substantial, additional explicit support for the company by AIHL.

During the second half of 2008, AIHL management reached the decision to revise ASIC's business plan and re-affirm AIHL's commitment to writing the surplus lines business that ASIC had voluntarily ceased writing as of January 1, 2008. Substantially all new and renewal excess and surplus lines business that had been written by ASIC in prior years was written, as of that date, by another foreign affiliate, Aspen Insurance UK Limited (AIUK) (United Kingdom). This business will now, again, be written by ASIC.

Both of AIHL's non-U.S. operating companies currently maintain FSRs of A (Excellent) and ICRs of "a". The ratings of ASIC also reflect its strong stand-alone capitalization, driven by its low underwriting leverage and negligible investment leverage.

These positive rating factors are partially offset by the weaker than expected results reported by ASIC during its initial period of operation, as evidenced by the company's inability to produce calendar year results in line with those detailed in the business plan shared with A.M. Best. Furthermore, the current competitive market also presents a significant challenge.

For Best's Credit Ratings, an overview of the rating process and rating methodologies, please visit www.ambest.com/ratings.

The principal methodologies used in determining these ratings, including any additional methodologies and factors, which may have been considered, can be found at www.ambest.com/ratings/methodology.

Founded in 1899, A.M. Best Company is a global full-service credit rating organization dedicated to serving the financial and health care service industries, including insurance companies, banks, hospitals and health care system providers. For more information, visit www.ambest.com.