A couple months ago, Rockstar, a patent-holding consortium backed by Apple, Microsoft, Sony, Blackberry, and others launched a barrage of infringement suits against Google and the makers of Android devices. Google has now launched a counteroffensive, seeking protection from Rockstar's patent trolling. The complaint (PDF) says, "Rockstar produces no products and practices no patents. Instead, Rockstar employs a staff of engineers in Ontario, Canada, who examine other companies’ successful products to find anything that Rockstar might use to demand and extract licenses to its patents under threat of litigation." Google's filing also accuses Rockstar of interfering with their business practices by contacting other companies and trying to convince them not to use Android. It asks for a declarative judgment of non-infringement.