Addressing the intersection of claim scope and prosecution history estoppel for design patents, the US Court of Appeals for the Federal Circuit found that prosecution history estoppel does not preclude enforcing a broader claim against a competitor, even if narrower subject matter surrendered during prosecution may have been more applicable. Advantek Marketing, Inc. v. Shanghai Walk-Long Tools Co., Case No. 17-1314 (Fed. Cir. Aug. 1, 2018) (Newman, J).

Advantek owns a design patent directed to an octagonal-shaped portable animal kennel that Advantek sells with the mark "Pet Gazebo." During prosecution of the patent, the US Patent and Trademark Office issued a restriction requirement identifying two designs: a dog kennel without a cover and a dog kennel with a cover. Advantek noted disagreement with the restriction requirement, but complied by electing the dog kennel without a cover for prosecution. The drawings and photograph submitted with the design application show that a frame forming the dog kennel without a cover is the same frame defining the dog kennel with a cover. Ultimately, the design patent issued and was directed to a dog kennel without a cover.

Advantek sued its former manufacturer, Shanghai Walk-Long Tools, along with others, for infringement of the design patent. The complaint alleged that Walk-Long copied the Pet Gazebo and infringed the patent with its "Pet Companion" product, which is a dog kennel with a cover. Walk-Long filed a motion for judgment on the pleadings, arguing that since the Pet Companion included a cover, prosecution history estoppel precluded infringement. The district court granted the motion and dismissed the complaint, finding that Advantek had surrendered the proposed kennel with a cover to secure the patent by choosing the drawings of the design without a cover in response to the restriction requirement. Advantek appealed.

Advantek argued that Walk-Long's accused kennel fell outside any claim scope that it purportedly surrendered during prosecution since the elected design was the "skeletal structure design," and that design was present in the accused kennel, with or without a cover. Advantek also noted that the accused kennel as shipped, assembled and used did not have a cover unless or until the cover was placed on the kennel. Advantek also argued that the requirements of prosecution history estoppel were not met because the election during prosecution broadened its ability to prevent infringement of the skeletal design, whether the skeleton was used with or without a cover.

The Federal Circuit agreed with Advantek, finding that Advantek elected to patent the ornamental design of a kennel with a particular skeletal structure, and that a competitor that sells a kennel embodying the patented structural design infringes the patent, regardless of extra features—such as a cover—that might be added to the kennel. The Court thus concluded that Advantek was not estopped by the prosecution history from asserting the patent against Walk-Long's products.

Practice Note: Enforcement of a granted design patent of a non-elected narrow embodiment is not precluded by the election of a broader embodiment during prosecution.

In The Doghouse: Prosecution History Estoppel, Design Claim Scope Are Different Inquiries

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