Billionaire investor Warren Buffett's (search) holding company said Thursday the U.S. Securities and Exchange Commission is asking for information about its subsidiary General Re Corp.

Buffett is chairman of Omaha-based Berkshire Hathaway Inc. (BRKA). The company said in a news release that the commission wants documentation and information relating to nontraditional or loss mitigation insurance products from General Re (search) and all its affiliates.

Federal and state regulators have been examining loss mitigation products to see whether insurance companies sold products that may not really be insurance, but instead may be aimed at helping companies smooth out earnings.

An SEC spokesman, John Nester, said the agency would have no comment.

"It is our policy to neither confirm nor deny the existence of investigations," Nester said.

Marc Hamburg, Berkshire's chief financial officer, did not immediately return a message seeking further comment.

General Re spokesman Charlie Agin referred questions to Berkshire.

General Re, based in Stamford, Conn., is one of the four largest reinsurance companies in the world.

Berkshire Hathaway shares fell $500 to $88,300 Thursday on the New York Stock Exchange.