eldavojohn writes "Thinking about developing a game involving a 'database driven online distributed tournament system?' Well, you had better talk to Walker Digital or risk a lawsuit, because Walker Digital claims to have patented that 'invention' back in 2002. The patent in question has resulted in some legal matters for the makers of 'Call of Duty: Modern Warfare 1 and 2, Call of Duty: Black Ops, Call of Duty: World at War, Blur, Wolfenstein, DJ Hero 2, Golden Eye 007, World of Warcraft and its expansions, Mafia Wars, and many others.' Walker Digital (parent company of Priceline.com) said it's not sure how much damages are going to be, and requested that through discovery in the court. If you think Walker Digital is not a patent troll, check out their lawsuit from two months ago against Facebook for using privacy controls Walker Digital claims to have patented. It would seem that any online competitive game that uses a database to select and reward contestants in a tournament could potentially fall under this patent — of course, those with the deepest coffers will be cherrypicked first."