Creative appears to have a patent on a shadowing technique similar to id Software's Doom 3 shadowing technique.
Creative apparently has a patent on a shadowing technique that appears to have some similiarity with id Software's soon-to-be-available DOOM3's shadowing technique (story). Now, without attempting to raise any controversy on this matter, this reporter thinks that software patents in general are a Bad Thing. It is a little suspicious that Creative posted about their technique on their company's developer forum first. To have later filed a patent and then challenge id Software is in this reporter's opinion inexcusable. This is tantamount to blackmailing game developers -- inventing a technique, talking about it before filing a patent that hasn't been published and then telling a game developer that there is some infringement is just unethical behaviour.
More information about this issue can be found at Beyond3D
Just another example why software patents suck..
Also this story might have something to do with this story regarding the cooperation of id Software and Creative to make Eax Advanced HD audio options for the Doom 3 engine.