LG has filed a complaint against Sony with the US International Trade Commission (ITC), claiming the PlayStation 3 and Bravia line of television models infringe as many as four Blu-ray Disc patents. The South Korean company is demanding a permanent ban of the PS3 from the US market.

LG has also filed a separate lawsuit with the US District Court in the Southern District of California, which covers other, non-PS3 devices, including PCs and digital cameras. You can read the full complaint, titled "Certain Electronic Devices Having a Blu-Ray Disc Player and Components Thereof" (PDF), courtesy of ITC Blog.

LG, which boasts that it owns 90,000 patents worldwide, appears to be taking this step in retaliation for a previous Sony complaint about various LG smartphones made last December, which the ITC is already investigating. As a result, the counterattack could be simply in the name of revenge, or at least that's what some are speculating. Clearly the best way to fight a patent complaint is to file a completely unrelated one.