Bermuda-based reinsurer Aspen Insurance Holdings Ltd. has announced the appointment of John Cavoores as co-chief executive officer of its insurance operations, Aspen Insurance.

Mr. Cavoores, who has been a member of Aspen's board of directors since 2006, will share oversight with fellow co-CEO Rupert Villers, effective immediately.

In a stetement, Aspen said: "The new structure will further strengthen Aspen's ability to grow its insurance business, subject to market conditions, as part of the company's broader diversification strategy."

Mr. Cavoores will have a particular focus on Aspen Insurance's casualty and professional lines businesses, while Mr. Villers will concentrate on transportation-related lines (marine, energy and aviation) and financial lines, with joint responsibility for property business.

In addition, Mr. Cavoores and Mr. Villers will also share responsibility on a geographic basis.

Mr. Cavoores, who is based in the US, will assume executive oversight for Aspen Insurance's US platform with Mr. Villers, who is based in the UK, responsible for non-US based operations. All other responsibilities within Aspen Insurance remain the same.

"Rupert and John are two of the insurance industry's most seasoned Executives and Aspen is fortunate to have both of them leading our insurance operations," said Chris O'Kane, CEO of the parent company, Aspen Insurance Holdings.

"Rupert was influential in our decision to restructure Aspen Insurance at the start of the year and he has had a considerable impact on our insurance operations overall. We are very pleased that, under the new structure, we will continue to benefit from Rupert's leadership, experience and counsel as we develop Aspen Insurance further.

"I am also delighted that John Cavoores will become co-CEO of Aspen Insurance," continued Mr. O'Kane. "As a board member and member of our risk committee, John has intimate knowledge of Aspen's operations and has been instrumental in the formulation of our strategy. We look forward to his contributions as we seek to capitalise on the investment we have made in our insurance business."

Mr. Cavoores joined AsMr. Cavoores joined Aspen's board in 2006 with nearly 30 years of experience in the insurance industry. He was an adviser to Blackstone on current portfolio investments and new opportunities in insurance from 2006 until August this year and a director of Alliant Insurance Holdings.

Previously, he was president and CEO of OneBeacon Insurance Company, a subsidiary of the White Mountains Insurance Group. He also was president of National Union Insurance Company, a subsidiary of American International Group.

"We are continuing to build out Aspen's US insurance platform selectively, most recently with the addition of admitted market capacity," Mr. Villers said.

"We are also working to round out our London market portfolio and have recently established a UK regional platform and a foothold in Switzerland."

Ÿ Credit rating agency AM Best Co. has affirmed the financial strength rating of A (excellent) of Aspen Specialty Insurance Company, a US subsidiary of Aspen Insurance Holdings. The outlook is stable.

Best said the ratings reflect ASIC's role and strategic importance to Aspen's overall strategy and support provided through substantial quota share reinsurance by Aspen Insurance Ltd.

"ASIC maintains strong stand-alone capitalisation, driven by its low underwriting leverage and negligible investment leverage, and solid liquidity," Best commented.

"However, the current competitive market presents a significant challenge to a company still seeking to firmly establish itself in the surplus lines/specialty market."