In addition, the isolation and sale of asbestos-laden subsidiaries is not available to competitors such as St. Paul Travelers and American International Group, he wrote.

In a similar vein, Bear Stearns analyst David Small said the deal underscored ACE's “creativity and determination in handling the company's legacy asbestos liability issues.”

But that “creativity” did not sit well with American International Group, Allstate, Chubb and St. Paul Travelers, who sent a joint letter early last year to Pennsylvania Insurance Commissioner Diane Koken, urging her to disapprove the sale.

Through the proposed sale, ACE was trying to skirt its obligations to its policyholders and diminish the clout the Pennsylvania department would have in enforcing them, the letter asserted.

Mr. Wilt noted the sale was approved with as little fanfare as possible in the middle of the Fourth of July weekend.

As a result of the sale, the ACE Group of Companies has reduced its exposure to legacy liabilities, including asbestos, by about $900 million, and has reduced its reinsurance recoverables by about $400 million.

The sale followed certain approvals by the U.K.'s Financial Services Authority and the Pennsylvania Department of Insurance. Both regulators approved the sale of the companies within their jurisdiction after concluding that the companies were adequately capitalized and that Randall & Quilter was a fit buyer.