“Whether this is a case ‘arising under’ federal patent laws under 28 U.S.C. § 1338(a) within the Federal Circuit’s jurisdiction under 28 U.S.C. § 1295(a)(1) when cross-respondents chose not to remove an earlier, underlying state court breach-of-contract case and instead litigated for four years in state court and then, on the eve of the state court jury trial after discovery closed, filed this federal declaratory judgment action claiming that inoperative contractual language transformed this breach-of-contract claim into a patent case within the exclusive jurisdiction of the federal courts.”
