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Vanderbilt University Law School




Can an appellate court alter substantive law without writing an opinion? We attempt to answer that question by conducting a novel empirical investigation into how the Federal Circuit has implemented the Supreme Court’s 2014 ruling in Alice v. CLS Bank, the most recent in a series of Supreme Court decisions strengthening patent law’s patentable subject matter requirement. Our dataset includes each one of the Federal Circuit’s more than 100 decisions on patentable subject matter in the three years since Alice, including affirmances issued without an opinion under Federal Circuit Rule 36.

Including those no-opinion affirmances, the Federal Circuit has found the patent to be invalid in more than ninety percent of its decisions. The court’s precedential opinions, however, tell a different story: nearly a quarter of them favor the patentee by rejecting challenges to patent validity. This difference is due largely to one remarkable fact: Although the court has issued over fifty Rule 36 affirmances finding the asserted patent to be invalid, it has not issued a single Rule 36 affirmance when finding in favor of a patentee. Rather, it has written an opinion in every one of those cases.

As a result, the Federal Circuit’s precedential opinions provide an inaccurate picture of how disputes over patentable subject matter are actually resolved. Those opinions suggest that any given patent has a decent chance of surviving an eligibility challenge at the Federal Circuit. But, in reality, very few patents do. Our findings suggest that, by saying nothing, a court can indeed affect substantive law, or at least the perception of it. This has interesting implications both for the on-going debate over the legality of Rule 36 and, more broadly, for understanding the differences between the law on the books and the actual experience of litigants.

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