Recent Developments in Patent Law 2020
In this appeal from the District of Delaware, the Federal Circuit (Judges Dyk and Taranto) affirmed the claims for propeller shaft vibration attenuation liners were patent ineligible for being directed towards Hooke's law, a law of physics concerning elasticity, without an inventive concept. Judge Moore dissented.
American Axle & Manufacturing's ("AMM") '911 patent involved a "method for manufacturing driveline propeller shafts ('propshafts') with liners designed to attenuate vibrations through a shaft assembly." Propshafts in operation generate noise through three different modes of vibration at different frequencies. Prior art used liners or weights to dampen individual modes of vibration. The '911 patent claims included an instruction to "tune" a liner to dampen two modes of vibration at once. The district court found the claims were essentially just a direction to apply Hooke's Law, a law of physics describing an object's elasticity and vibration frequency, and did not provide a means of crafting the liner or propshaft. Because the claims were directed toward a law of nature without an inventive concept, the district court help the patent invalid.
