UNITED STATES: Federal Circuit Rules on Prosecution History Estoppel in Top Brands v. Cozy Comfort

In Top Brand LLC, et al. v. Cozy Comfort Company LLC, et al., Case No. 2024-2191, the United States Court of Appeals for the Federal Circuit ruled that Cozy Comfort’s arguments to the U.S. Patent and Trademark Office (USPTO) to obtain allowance of the asserted design patent narrowed the scope of the patent and precluded infringement. The Federal Circuit reversed the district court’s denial of judgment as a matter of law of non-infringement and held that no reasonable jury could have found infringement of the design patent due to Cozy Comfort’s surrender of claim scope during prosecution.

Cozy Comfort had brought claims for infringement of a design patent for “an enlarged over-garment with an elevated marsupial pocket” against Top Brand’s oversized wearable blanket. At trial, a jury found infringement. However, Top Brand asked the district court for a judgment of non-infringement as a matter of law. The district court denied that motion and Top Brand appealed to the Federal Circuit, arguing that the district court erred by:

• Failing to instruct the jury on a verbal claim construction limiting the asserted design patent based on Cozy Comfort’s statements during prosecution; and
• Denying judgment of non-infringement as a matter of law.

The Federal Circuit reversed the district court’s judgment of infringement and held that the court erred in not applying the doctrine of prosecution history estoppel to the design patent. Specifically, during prosecution of the design patent, the USPTO had rejected the claimed design over a prior art patent, and Cozy Comfort only overcame that rejection by arguing that specific features distinguished the claimed design from the prior art.

As the Federal Circuit explained, the “doctrine of prosecution history disclaimer is well established for utility patents and addresses surrender of claim scope during prosecution of a patent.” The Federal Circuit had previously held that prosecution history estoppel applies to design patents where an applicant responds to a rejection in a design patent application by deleting figures associated with all but one patentably distinct design. In that case, the patentee narrowed the scope of the design patent and surrendered the deleted subject matter.

Cozy Comfort argued the prosecution history estoppel should not apply because Cozy Comfort did not delete any figures or make any amendment to the application, and prosecution history estoppel requires an unambiguous disavowal of claim scope. However, the Federal Circuit rejected that argument and found that Cozy Comfort’s arguments during prosecution were, in fact, an unambiguous disavowal of claim scope. The Federal Circuit explained that during prosecution “Cozy Comfort explained how its design differed from [the prior art] by focusing on specific distinguishing features such as the shape and placement of the marsupial pocket and shape of the bottom hem line. In making these arguments, Cozy Comfort surrendered the identified features as supporting a finding of overall similarity.”

With this decision, the Federal Circuit made clear that prosecution history estoppel applies to design patents based on arguments made by the patentee during prosecution even if the patentee did not amend the application.

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