full story at : http://gizmodo.com/5549129/irony-warner-bros-sued-for-pirating-anti+pirating-technology

picture comes from : http://reporter.blogs.com/

In 2003, a company named Medien Patent Verwaltung showed Warner Bros. their technology to mark films in a way capable of tracing a pirated copy back to its origin theater. And allegedly, WB has been using the tech since...without paying.
MPV has a patent on their technology and is suing with that in hand. Interestingly enough, WB has a patent on some sort of "Motion Picture and Anti-Piracy Coding" as well.