The Supreme Court has told us that obviousness in patent cases is a question of law, based on underlying findings of fact. What this means is that juries as fact-finders are supposed to decide the underlying factual issues, but judges are supposed to decide the ultimate legal question of patent validity. See KSR Inter., Co. v. Teleflex, Inc., 550 U.S. 398, 427 (2007). It seems like a straightforward division of responsibility; the reality, however, is far more complicated.