A method of manufacturing driveshafts to reduce vibrations wasn’t patent-eligible, the Federal Circuit said Oct. 3.
The patent only described a general application of natural law, according to the majority opinion.
American Axle & Manufacturing Inc. owned U.S. Patent No. 7,774,911, covering a method for manufacturing propshafts so they make less noise. The shafts have liners that vibrate at matching frequencies to damp their vibrations. Propshafts vibrate in three different “modes,” and AAM said the patent described a new method for tuning a liner to damp vibrations from multiple modes simultaneously.
Neapco challenged the validity of the patent claims during...