The United States Supreme Court heard oral argument (transcript here) this week on what is probably the most significant legal malpractice case it has considered in several years. As we have previously written the Supreme Court granted certiorari from a Texas Supreme Court case, Minton v. Gunn, to address the question of federal court exclusivity for a legal malpractice action arising out of a patent case. Legal malpractice is generally a state law tort claim, but the federal courts have jurisdiction over claims arising under the patent laws. The question, therefore, is whether the legal malpractice action “arises under” the patent law. The main question in the case is what amounts to a “substantial issue” which would require the federal court to exercise jurisdiction of what would otherwise be a state law claim. One of the main concerns of the justices is whether allowing the state court to decide the matter would create a situation where a state court might create new law on patents, as opposed to having a federal court potentially create new case law on legal malpractice.