Washington Attorney General Rob McKenna says he's suing the makers of Samsung, Toshiba, Sharp and five other brands of liquid crystal display screens.
McKenna says they engaged in price-fixing.
The lawsuit was filed Wednesday in King County Superior Court following a yearlong investigation by Washington and other states. It alleges that company leaders regularly met in secret to agree on prices and limit production from 1998 to 2006, and it seeks restitution for state agencies and consumers as well as civil penalties.
Several of the companies and their executives have already pleaded guilty to federal criminal charges.
The defendants in Washington's case include Epson Electronics America Inc., Hitachi Displays Ltd., LG Display America Inc., Toshiba Corp. and Samsung Electronics Company Ltd.