I think protomyth was referring to the fact that while the Theora folks loudly claim to be unencumbered by patents this is a completely untested assertion and if such a patent were to show up they are without their own suite of patents with which to threaten the other party.  MPEG-LA is covered by patents and has a licensing board, but the spec is also pretty-well vetted by various teams of lawyers and if someone tries to submarine a patent in they would find themselves facing a rather large, well-funded, and pissed off group with no qualms about burying the troll in counter-claims and long/expensive discovery, etc.