REUTERS/Rick Wilking
Berkshire Hathaway Chairman Warren Buffett is surrounded by the press as he wanders the company trade show before his company's annual meeting in Omaha, Nebraska April 30, 2011. Dozens of BH companies had displays in the building next to the site of the meeting.
The designation, which Treasury has already given to AIG, GE, and Prudential, means Berkshire would come under Federal Reserve regulation.
Berkshire's class-A shares have a market cap of $285 billion, and the firm is the fourth-largest reinsurer in the world.
Bloomberg says any decision would be months away.