A joint venture of Hitachi Ltd and LG Electronics pleaded guilty to 15 criminal counts in connection with a long running probe of price fixing in the sale of optical disk drives.

Hitachi-LG Data Storage Inc is the first company charged by prosecutors in the investigation.

District Judge Richard Seeborg accepted the plea from the company on Tuesday at a hearing in San Francisco. Seeborg sentenced the company to a $21.1 million fine.

Cristina Arguedas, an attorney for the company, declined to comment after the hearing.

Major companies including Sony, Hitachi and Toshiba disclosed in 2009 that they had received subpoenas from the Justice Department related to the investigation of sales of disk drives, such as CD, DVD and Blu-ray players.

Hitachi-LG Data Storage Inc also agreed to assist with the ongoing investigation. In a court filing, the Justice Department said the company deserved its low fine because of the substantial assistance it is providing to the government.

The joint venture admitted conspiring with others to eliminate competition or fix prices for drives sold to computer giants Dell, Microsoft and Hewlett Packard dating back to 2004.

The venture was also charged with participating in a scheme to defraud HP during one procurement event in 2009.

The case is: USA v. Hitachi-LG Data Storage Inc, No. 11-cr-724 in U.S. District Court for the Northern District of California.