Groups of Chicago lawyers are urging the nation’s top court to clear up one of the biggest issues in patent law.The Intellectual Property Law Association of Chicago as well as a separate group of four Chicago patent attorneys have filed briefs asking the U.S. Supreme Court to clarify how far removed from nature an innovation must be in order to be eligible for patent protection.Right now, “confusion reigns” on the topic, the association wrote in its friend-of-the-court brief submitted late last week …