ShackNews is reporting Activision Blizzard is being sued by Worlds Inc., for violating a patent on virtual worlds. The firm claims that games like Call of Duty and World of Warcraft violate its patent, and are requesting "fair compensation." The patent covers a "system and method for enabling users to interact in a virtual space," reports Games Industry International. That may sound broad, but the company did manage to get an undisclosed settlement out of NCSoft for City of Heroes in 2010. "Technologies created by Worlds have helped the businesses of virtual worlds gaming and the sale of virtual goods to grow into a multi-billion dollar industry," said Worlds CEO Thom Kidrin. "While we are pleased to see that the gaming industry and its rapidly growing customer base have enthusiastically embraced our patented technologies, we deserve fair compensation for their use." No response yet from Activision Blizzard.