In our Information Letter N.S. 181, we reported that in the case of Sun Hill Industries v. Easter Unlimited Inc. the district court reaffirmed that the doctrine of equivalents is applicable to design patents and held that the design patent for a jack-o-lantern bag for collecting lawn refuse showing happy and sad faces was infringed under the doctrine of equivalents by a bag that had only one face and also lacked some other features of the drawings.

This decision has now been reversed by the Court of Appeals for the Federal Circuit. The Federal Circuit noted that to find infringement of a design patent, the accused product must be compared to the claimed design to determine whether the two designs are substantially the same. The Federal Circuit pointed out that the District Court had compared unclaimed features of the two bags in reaching its decision that there was infringement under the doctrine of equivalents. To find infringement, the allegedly infringing product must incorporate the point of novelty of the claimed design. Since the allegedly infringing product did not have any of the novel features of the claimed design, there was no literal infringement and no infringement under the doctrine of equivalents of Sun Hill's design patent.