Lawnmower Steering Patent Invalidation Reversed by Federal Circuit

Written August 15, 2019

The Federal Circuit on August 12, 2019, reversed the Patent Trial and Appeal Board’s (PTAB) invalidation of patent claims covering a lawnmower steering mechanism, holding that the Board’s decision was “predicated on its incorrect claim construction” of the term “mechanical control assembly.” MTD Prods. Inc. v. Iancu, Fed. Cir., No. 17-2292, 8/12/19. 

The Toro Company, an American manufacturer of gardening equipment, sought inter partes review of MTD Products Inc.'s U.S. Patent No. 8,011,458, which covers a steering and driving system for zero-turn radius lawnmowers. The PTAB found the claims in question invalid based on prior art.

On appeal, MTD argued that the PTAB should have found the claim term “mechanical control assembly” to be a means-plus-function term that wasn’t disclosed in the prior art.

The Federal Circuit agreed, finding that “the Board erred by using the existence of corresponding structure in the specification to conclude that ‘mechanical control assembly’ has a sufficiently definite structure” and wasn’t a means-plus-function claim.

File Downloads