Endurance Specialty Holdings Ltd., a Bermuda company selling property and casualty insurance and reinsurance, said two of its initial investors, Texas Pacific Group and Thomas H. Lee Partners, are selling 7.7 million of its shares in a block trade.

The sale of the Endurance shares is being handled by Goldman, Sachs & Co. , who will sell the shares to public investors. Endurance will not receive any proceeds from the sale, which represents about 13 percent of the company's total outstanding shares.

Endurance was one of a dozen highly capitalised insurance and reinsurance ventures to be set up in Bermuda following a severe void in insurance capacity, after some $32.5 billion in claims from the September 11, 2001 terrorist attacks. Some of Endurance's peers have also seen founding investors sell off their shares, while others have returned capital to their shareholders as the insurance cycle begins to soften. In a soft market, the opportunity to sell policies for a profit tightens, as increasingly cut-throat competition reduces the market rates for a wide range of insurance policies.

Thomas H. Lee Partners was an investor in Endurance as well as one of its 2001 peer companies, AXIS Capital Holdings Ltd. It no no longer holds its stake in the latter.