Hitachi, Toshiba and Sony said Tuesday that their optical disk drive operations in the U.S. received subpoenas from the U.S. Department of Justice in an investigation into potential antitrust violations. Sony Optiarc America, which supplies a lineup of optical disc drives, has received a subpoena from the U.S. Department of Justice's antitrust division.

The company, which is the result of a joint venture between Sony and Nec in the optical disc drive field, did not comment on whether the investigation included Blu-ray products.

Japanese giants Hitachi and Toshiba also said separately Tuesday that their optical disk drive businesses in the U.S. would fully cooperate with the inquiry.

Hitachi has a 51%-owned optical storage joint venture with LG, in a company called Hitachi-LG Data Storage. In addition, Toshiba's is a 51%-owned joint venture with Samsung called Toshiba Samsung Storage Technology Corp.

Although none of the companies provided details on the subpoenas, the WSJ wrote on Tuesday that the criminal antitrust probe into the market for optical disk drives had been started by the U.S. Department of Justice some months ago, investigating disc-drive makers for possible price-fixing, bid-rigging and allocation of markets.