DRM tech firm Uniloc last week filed a patent infringement suit against game publishers and other software companies, according to court filings obtained by Gamasutra. Irvine, CA-based Uniloc USA and its Singapore parent are suing Call of Duty publisher Activision Blizzard and Mac game specialist Aspyr over alleged infringement of a patented anti-piracy product activation method for software. Other defendants named in the suit are Sony Corporation of America, Sony DADC, Borland Software, McAfee and Quark. The lawsuit accused the companies of implementing a product activation and registration system that infringes on Uniloc's patent. The suit comes amid a six-year legal battle with Microsoft, which Uniloc also accused of infringing on the same patent, "System for Software Registration." In 2009, a jury awarded $388 million to Uniloc, but a judge overturned the decision five months later. Uniloc is appealing the decision. The suit alleged that all defendants "willfully" infringed on the patent, because they were all aware of the high-profile Microsoft case, and have "acted despite an objectively high likelihood that its actions constitute infringement of the [patent]." "Patent infringement, especially when it's carried out by 'Captains of Industry' like Sony America and McAfee can kill a small business," said Uniloc CEO Brad Davis in a statement last week. "We do not intend to let this happen to Uniloc and we plan to defend our patents aggressively whenever we believe they are violated." Uniloc's technology has been used in games including Sega's Alpha Protocol and Football Manager 2009 for PC, and casual PC titles from Namco Networks and Merscom. Merchant & Gould intellectual property attorney Eric Chad told Gamasutra that Uniloc may have a legitimate case against the defendants. "Uniloc's complaint is very conclusory, so it's hard to determine the merits of their claims of infringement, but if the notorious Uniloc vs. Microsoft case is any indication, the case likely has enough legs to get to trial if the parties don't settle," Chad said. The attorney speculated that that Uniloc would likely say there are "hundreds of millions of dollars" at stake here. The defendants, he guessed, would argue the stakes are much lower, around a few million dollars. Uniloc is asking the court to enjoin "unlawful acts of infringement" and award damages and legal fees. Chad added, "In the Microsoft case, the claims went to trial and Uniloc obtained a jury verdict and a damages award of nearly $400 million, but the court overturned the jury's verdict. There's no reason, at this point, to believe that Uniloc's claims are any less viable in this case."