So remember how Facebook was tracking users even after they’d logged out? And after the outcry, said it was a bug and that it was fixed? Was only last week, even.
Well check my link. Turns out, on 9/22/2011, just before the uproar began, Facebook filed for a patent. For what, you ask?
“A method is described for tracking information about the activities of users of a social networking system while on another domain.”