In a letter to two judiciary committees last week, a federal appeals court judge said that his colleagues on the bench who have holdings in Warren Buffet’s Berkshire Hathaway face a conflict-of-interest problem, and suggested changes to disclosure procedures.

Judge Ralph Erickson, of the U.S. Court of Appeals for the Eighth Circuit, said that judges invested in Berkshire Hathaway can be unaware that a company in a case before them is a subsidiary of the Omaha, Nebraska-based conglomerate.