Sony said it "has received a subpoena from the U.S. Department of Justice (DOJ) Antitrust Division seeking information about its static random access memory (SRAM) business. Sony intends to cooperate fully with the Justice Department in what appears to be an industry-wide inquiry."

No additional details were available immediately about the Justice Department's investigation. Last year, Samsung pleaded guilty and agreed to pay a $300 million fine in connection with DRAM price fixing in a separate Justice Department anti-trust matter.