(CN) – The Federal Circuit revived Vita-Mix’s patent lawsuit against a competitor over plungers meant to stop air pockets from forming in food blenders.
Vita-Mix makes the Vita-Mix 5000, which includes a plunger to block the air channel typically formed around the blender’s moving blades.
It accused Basic of violating its patents and trademarks with the Smoothie Elite, the Smoothie Plus and the Blender Solutions 5000, which come with a “stir stick” that resembles Vita-Mix’s plunger.
U.S. District Judge Patricia Gaughan in Ohio found Vita-Mix’s patents valid, and ruled that Basic’s blenders didn’t violate patent or trademark.
The federal appeals court in Washington, D.C., agreed that Vita-Mix failed to prove trademark infringement, inducement or contributory infringement, but vacated the lower court’s finding of direct infringement.
Gaughan had discounted the testimony of a Vita-Mix expert, whose survey found that some Basic blender users left the stir stick in the pitcher without stirring it. The parties agreed that this manner of use would infringe on Vita-Mix’s patents.
In ruling for Basic, Gaughan cited the lack of testimony or footage showing actual infringement.
“Such evidence, however, is not required,” Judge Prost wrote for the appellate panel. “Direct infringement can be proven by circumstantial evidence.”
The court also vacated and remanded the finding that Vita-Mix’s patents were “not invalid.”
Judge Bryson filed a partial dissent, saying Vita-Mix presented enough evidence to survive summary judgment on its claims for inducement and contributory infringement.