What Matters Under the Ordinary Observer Test: Similarities, Differences, or Both?

Introduction

The Court of Appeals of the Federal Circuit (CAFC) recently reaffirmed the standard used for design patent infringement analysis in Range of Motion Products, LLC v. Armaid Company Inc., Case No. 2023-2427 (Fed. Cir. Feb. 2, 2026). However, a dissent by Chief Judge Moore potentially augurs a future change in the standard.

The Case

Range of Motion accused Armaid’s “Armaid2” full body massager of infringing their design patent. The district court found that there was no infringement.

The CAFC affirmed the decision, agreeing that the design patent was not infringed because there were substantial differences between the two designs.

Image Courtesy of the Majority Opinion

The Law

Infringement of a design patent is governed by the “ordinary observer” test laid out by the U.S. Supreme Court in Gorham Co. v. White, 81 U.S. 511, 528 (1871).

The ordinary observer test stipulates that a design patent is infringed if an ordinary observer, giving such attention to the product as a purchaser normally gives, would be deceived by the resemblance between two designs into purchasing one design, presuming it to be the other. In other words, under the ordinary observer test, if a first product’s design induces a person to buy that first product thinking it is a different, second product, the first product infringes the design of the second product.

However, the ordinary observer test hides some wrinkles. One important wrinkle is that the “design” of the design patent must be construed by the court in a process called claim construction. When construing the claims in this way, functional elements of the design are excluded from the infringement analysis. It is the claim construction step that allows us to understand the decisions from Judge Levy and the Court of Appeals.

The Decision

The district court initially compared the design to Armaid’s product and noted they were quite similar. However, the district court also found that many of the similarities between the designs were due to functional aspects that could only be considered to the extent they contributed to the overall ornamentation of the design. For instance, the district court asserted that the arc of the clamshell arms was functional. Thus, the district court strongly suggested, and the Court of Appeals agreed, that the overall shape, being primarily determined by functional components of the design, would then be ignored or minimized when evaluating the similarity of the two designs.

Both the district court and the Court of Appeals then identified the following differences between the two designs:

• The base of the Armaid2 is larger and more rectangular proportionally compared to the claimed design;
• The Armaid2 has a more segmented appearance because of internal partitions in the arms;
• The size-selection slots (in the Armaid2’s base) are larger both on their own and proportionally to the product as a whole; and
• The blunter, less rounded end of the hinge apparatus of the Armaid2 is more eye-catching than the subtler, rounder curves of the hinge apparatus in the claimed design.

Based on these differences, the district court and the Court of Appeals found that the overall designs were distinct from one another and concluded that there was no infringement.

The Dissent

The dissent, on the other hand, argued that a reasonable factfinder could find infringement because of the overall visual similarity between the designs.

The Ordinary Observer Test, as laid out in Gorham, requires comparing the substantial similarity of two designs, not the differences. As the dissent observed, a focus on differences emphasizes the differences and minimizes similarities, while a focus on similarities produces the opposite result.

This is illustrated by the following image, provided by the dissent (and originally from https://fliphtml5.com/fwspv/ktmi):

When focusing on the differences, there are many subtle differences that are easy to find (the mirrors are different shapes, arms are in slightly different positions, hair colors are different, and so forth). However, when focusing on the similarities, it is easy to point out all the similarities between the two images (the placement of the table in the foreground, the overall composition of the image, similar fur colors, similar hair designs, and so forth). The dissent would have focused on these similarities.

The Federal Circuit could reconsider the design patent infringement analysis sometime in the future if enough judges agree with the dissent.

So, Are Design Patents Worthwhile?

Given the apparent similarity between the claimed design and the Armaid2 product, and the finding of noninfringement, one might consider whether pursuing a design patent is worthwhile. The short answer, often, is yes.

Design patents are a powerful and valuable tool to round out any patent portfolio and can be useful for any business designing a visually distinct article, from confectionary to the latest heavy machinery.

The cost of acquiring a design patent is typically much lower than acquiring a utility patent, and design patents are almost always allowed by the U.S. Patent and Trademark Office. As a result, when a design patent generates a jury verdict, it does so at a lower upfront cost, in most cases.

Furthermore, a design patent protects the appearance of a product. If a product has a distinctive design, a design patent can ensure that counterfeiters cannot easily appropriate its appearance, even when designing around any utility patent coverage for the product. In other words, design patents can offer a different scope of protection than a utility patent.

Design patents remain an important tool in patent protection and litigation. In other words, if your product has a look that you value, that look is worth protecting.