In Hafco Foundry and Machine Co., Inc. v. GMS Mine Repair and maintenance, Inc., Inc., [2018-1904] (March 16, 2020), the Federal Circuit affirmed the judgment of infringement of U.S. Patent No. D681,684 for a “Rock Dust Blower, ” affirmed the of GMS’ request for a new trial, and remanded for a final judgment on damages.

On appeal, GMS argued that the jury instructions incompletely and prejudicially abridged the Gorham test,” and failed to instruct that the hypothetical ordinary purchaser is to view the patented and accused designs in the context of the prior art.

GMS complained that the jury instructions defined the ordinary observer as “a person who buys and uses the product at issue.” However GMS failed to object to this language or any explanation of the purported flaw. GMS also argued the jury should have been instructed that small differences between the accused and the claimed design will avoid infringement, but GMS did not ask for such an instruction, and in any event the Federal Circuit said that it was not correct, noting that the designs do not have to be identical for design patent infringement to be found.

As to GMS’s second point, it argued that the jury should have been instructed to “familiarize yourself with each of the prior art designs that have been brought to your attention,” citing IPO Model Design Patent Jury Instructions. However GMS did not introduce any prior art. The Federal Circuit said that given that there was no prior art introduced at trial, no attempt by GMS to introduce the prior art, and no proposed jury instruction on this issue, the purported exclusion of this instruction cannot be error.

The Federal Circuit affirmed the finding of infringement and remanded for a determination of the damages.