How prosecution history disclaimer doomed a patent infringement claim
Doctrine applies to both design and utility patents
A patent doesn’t always provide the protection a patentee expects. In fact, the prosecution history (all communication between the patent applicant and the examiner) can come back to haunt a patentee when it later pursues an infringement action.
Hoodie hullabaloo
Cozy Comfort Co. LLC owns a design patent for an “enlarged over-garment with an elevated marsupial pocket.” It is popularly marketed as “The Comfy.” Its patent application was initially rejected during prosecution because it was anticipated by another patent (the White design). To overcome the rejection, the company agreed that its design was similar but differed from the White design in some particular respects.
Cozy Comfort subsequently accused Top Brand of patent infringement. In response, Top Brand sought a declaratory judgment of noninfringement. Cozy Comfort counterclaimed for infringement. A jury found that Top Brand infringed the patent.
No pocket protector
On appeal, Top Brand argued that the trial court should have overridden the jury and granted it a judgment as a matter of law of no infringement, meaning no reasonable jury could find infringement. The question was whether the trial court erred by declining to interpret the design patent claim as limited by the doctrine of “prosecution history disclaimer.”
This doctrine allows a court to limit the scope of patent claims based on the prosecution history. The disclaimer can arise from claim amendments or arguments made to the Patent and Trademark Office. The doctrine is well established for utility patents, but Cozy Comfort argued that it doesn’t apply to design patents.
The Federal Circuit disagreed. According to the court, it would be contrary to the purpose of design patent prosecution to allow the patentee to make arguments in litigation that contradict the representations that led to the grant of the patent and later recapture surrendered claim scope.
The court next considered whether the doctrine applied in the case. The doctrine applies only to “unambiguous disavowals” during prosecution.
To obtain the patent, Cozy Comfort had explained how its design differed from White by focusing on distinguishing features, including the shape and placement of the marsupial pocket (the pocket on the front of a sweatshirt) and the shape of the bottom hemline. The court determined that Cozy Comfort surrendered the identified distinguishing features.
Unfortunately for Cozy Comfort, the court found that multiple aspects of Top Brand’s allegedly infringing products were the same features that Cozy Comfort disclaimed during prosecution. The company, therefore, couldn’t rely on the features to show design similarity between the products.
Wrapped up
With the prosecution history disclaimer properly applied, the court said, the evidence permitted only one reasonable conclusion — no infringement. It therefore reversed the trial court and the jury’s verdict.
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