The most important determinant of a case’s chances for Supreme Court review is a circuit split: If two courts of appeals have decided the same issue differently, review is substantially more likely. But practically every appeal in a patent case makes its way to a single court—the Court of Appeals for the Federal Circuit. How, then, does the Supreme Court decide whether to grant certiorari in a patent case? The petitions for certiorari in the Court’s patent docket suggest an answer: The Supreme Court looks for splits anyway. These splits, however, are of a different sort. Rather than consider whether two courts of appeals have decided the same issue differently, the Court looks to whether two fields of law conflict over the application of the same transsubstantive doctrine. Such “field splits” are unusual candidates for Supreme Court attention. After all, the Court’s interest in circuit splits is motivated by a desire for geographic uniformity in federal law. But field splits, unlike circuit splits, do not give rise to forum shopping concerns, do not undermine the predictability of the law, nor otherwise implicate the legal values that counsel in favor of uniformity. Instead, the Supreme Court’s attention to field splits may suggest that legal universality—consistency across substantive fields of law—is an important (but unstated) priority in certiorari decisionmaking. The exercise of this universality interest through certiorari decisions in patent cases has several consequences for the Supreme Court’s agenda. The Court must better explain why field splits merit review, and we must better understand how to distinguish those field splits that implicate the Court’s universality- related concerns from those that do not.