Factoring Out of Functional Elements Proper in Design Patent Infringement Analysis

March 3, 2010 – Blog Post

The U.S. Court of Appeals for the Federal Circuit issued their second significant design patent opinion in the past two weeks. In the most recent decision, the Court affirmed a finding of no-infringement of a design patent after a district court had first construed the claim by factoring out the functional elements of the design. Richardson v. Stanley Works, Inc., No. 2009-1354 (Fed. Cir., Mar. 9, 2010).

The patent at issue (U.S. Design Patent No. D507,167) claimed the design for a carpentry tool known as a stepclaw. The stepclaw includes a handle, hammer-head, jaw, and crow-bar. The district court found that "the overall configuration of these four elements is dictated by the functional purpose of the tool and therefore is not protected by [Richardson's] design patent." Richardson v. Stanley Works, Inc., 91 USPQ2d 1604 (D. Az. 2009). The district court construed the claim to exclude any "primarily functional" elements.Id. at 1606. Regarding the jaw on the stepclaw, the district court noted that "none of the prior art designs are as similar to Richardson's patented design as is Stanley's." Id. at 1607. Often, the presence of alternative forms for a feature (e.g. a jaw) that performs a certain function suggests that the claimed form of the feature is ornamental. However, the district court also noted that "Richardson had to design the jaw the way he did...to function as 'a step to elevate the worker without a ladder.'" Id. Thus, the district court concluded that the "basic jaw design used by Richardson and Stanley...is primarily functional." Id. Regarding the features determined to be ornamental, the district court found "little similarity" and noted that the differences between the two tools are substantial to find infringement.

On appeal, the patent owner argued that the district court erred in separating out functional aspects of the design from the ornamental ones, rather than considering the design as a whole. The U.S. Court of Appeals for the Federal Circuit disagreed. The Court identified elements in the patented design that were "driven purely by utility." Slip Op. at 6. In support of its identification of "purely functional elements," the Court noted that the elements had been known in the prior art for over a century. Slip Op. at 7.

The Court instead compared only the ornamental aspects of the design to the accused tool. In affirming the district court finding of no-infringement, the Court explained "ignoring the functional elements of the tools, the two designs are indeed different. Each of the Fubar tools made by Stanley has a streamlined visual theme that runs throughout the design including elements such as a tapered hammer-head, a streamlined crow-bar, a triangular neck with rounded surfaces, and a smoothly contoured handled. In a side-by-side comparison with the ’167 patent design, the overall effect of this streamlined theme makes the Fubar tools significantly different from Richardson’s design." Slip Op. at 10.

The full text of the Richardson decision may be found at the above pdf link.