In late June, the U.S. Supreme Court denied certiorari in American Axle & Manufacturing v. Neapco Holdings, 939 F.3d 1355 (Fed. Cir. 2019), modified on pet. for reh'g, 967 F.3d 1285 (Fed Cir. 2020). The denial of certiorari lets stand a controversial decision of the U.S. Court of Appeals for the Federal Circuit concerning the law of patent eligibility. The certiorari denial is also significant for another reason: It represents a departure from the deference historically shown by the court to the case-selection recommendations of the U.S. Solicitor General.

The 'American Axle' Patent. The patent at issue in American Axle concerned a method for manufacturing a quieter automobile driveshaft. A driveshaft is a component of an automobile that transmits power from the engine to the axles and wheels. Because they are commonly made of thin-walled metal, driveshafts are susceptible to unwanted vibration and thus often produce unwanted noise. American Axle obtained a patent disclosing the insertion of a liner into the driveshaft and, in claim 22 of the patent, the subsequent "tuning" of that liner to produce frequencies that dampen vibration and reduce noise accordingly.

Divided Panel Decision and Denial of En Banc Rehearing. In 2019, a divided panel of the Federal Circuit held that claim 22 was not eligible for patent protection. Section 101 of the Patent Act renders patent-eligible "any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof."