Design Patent Infringement: How the Ordinary Observer Test Works
Design patent infringement is easy to describe and difficult to evaluate. The legal question is not whether two products perform the same job, share a broad concept, or contain several matching parts. The question is whether an ordinary observer, familiar with the relevant prior art and giving the attention a purchaser usually gives, would view the accused design as substantially the same as the patented design.
That visual test has governed design patent cases for generations, but its application remains contested. In Range of Motion Products v. Armaid, the Federal Circuit affirmed summary judgment of noninfringement on February 2, 2026. The court then denied rehearing en banc on August 11, 2026, leaving in place the rule that a court may resolve a case without a trial when no reasonable jury could find the designs substantially the same. Separate opinions disagreed sharply about when that conclusion is appropriate. The dispute is a useful reminder that a design patent case turns on disciplined visual comparison, not a tally of matching and different details.
The ordinary observer test asks about overall visual effect
The test comes from the Supreme Court’s 1871 decision in Gorham Co. v. White. In modern form, the Federal Circuit asks whether, in the eye of an ordinary observer giving the attention a purchaser usually gives, the two designs are substantially the same, with a resemblance capable of inducing the observer to purchase one supposing it to be the other.
In its en banc Egyptian Goddess v. Swisa decision, the Federal Circuit made the ordinary observer analysis the sole test for design patent infringement. It rejected the former “point of novelty” test as a separate requirement. A patent owner therefore does not have to isolate one novel feature and show that the accused product copied that feature. The factfinder instead evaluates the patented design as a whole.
“As a whole” does not mean that individual features become irrelevant. Courts may identify similarities and differences, but those observations must serve the ultimate comparison of overall visual impressions. A case can go wrong when a party treats every curve, opening, proportion, texture, or transition as a separate vote. Some differences dominate the appearance; others disappear in the overall effect. Their significance also depends on what the patent actually claims and what the prior art already showed.
Start with the patent drawings, not the commercial product
A design patent generally contains one claim: the ornamental design for the identified article, as shown and described. The drawings provide the visual definition of that claim. The USPTO calls the drawing disclosure a critical part of the application because it depicts the claimed design, and warns that a defective disclosure may not be repairable after filing.
That makes line choices consequential. Solid lines ordinarily show claimed subject matter. Broken lines can disclose unclaimed portions or environmental structure, depending on the drawing convention and accompanying description. Surface shading may communicate contour and character. Multiple views establish how the design relates in three dimensions. An infringement analysis should therefore compare the accused product to the claimed drawings, not merely to photographs of the patent owner’s product.
The distinction can change the result. A commercial embodiment may include logos, colors, materials, accessories, or later design changes that do not appear in the patent claim. Conversely, an accused product may omit unclaimed surroundings yet still reproduce the claimed ornamentation. Tucker Law’s guide to the basics of design patent law explains how the single claim and drawing conventions define the protected appearance. Those choices should be evaluated before filing through a coordinated patent application strategy, not after a competitor enters the market.
Function affects claim scope without turning the comparison into a parts list
Design patents protect ornamental design, not functional innovation as such. When a design contains both functional and ornamental aspects, the court construes the claim to identify the nonfunctional aspects shown in the patent. A feature may serve a useful purpose and still incorporate protectable ornamental choices in its shape, proportion, surface treatment, or relationship to other features.
The Federal Circuit’s Lanard Toys v. Dolgencorp decision illustrates the balance. The court may consider the ornamental features of individual elements, but it must ask how they affect the overall design. Discounting functional subject matter cannot convert the analysis into an element-by-element checklist.
This is one reason design-patent claim construction matters. A broad functional concept—such as a handheld massager with opposing arms, a hook that supports an object, or a pencil-shaped chalk holder—does not itself establish infringement. The protected scope lies in the ornamental appearance shown in the drawings. Tucker Law’s discussion of patent claim construction addresses the broader process by which courts determine claim meaning and scope before comparing a patent to an accused product.
Prior art supplies the visual frame of reference
The hypothetical ordinary observer is treated as familiar with the relevant prior art. That context prevents a patent owner from using a design patent to control an appearance that was already common while also helping the factfinder identify what gives the claimed design its distinctive visual effect.
When the claimed design is close to prior designs, relatively small differences between the patent and accused product may matter more. Imagine a field in which nearly every product has the same basic silhouette. A change in the base, handle transition, surface pattern, or proportions may carry much of the patent’s visual scope. In a less crowded field, those same differences may have less effect on the total impression.
This is sometimes described as a three-way comparison:
| Comparison | What it helps establish |
|---|---|
| Claimed design and accused design | Their overall visual similarities and differences |
| Claimed design and prior art | Which visual characteristics distinguish the claim from familiar designs |
| Accused design and prior art | Whether apparent similarity comes from the protected design or from features already present in the field |
The prior art must be reasonably relevant to the visual comparison. A collection of remote designs chosen only because each contains one matching feature can distort rather than clarify the ordinary observer’s perspective. Parties should develop the prior-art record early and be prepared to explain why each reference belongs in the observer’s field of vision.
Copying is important evidence, but it does not replace the test
Businesses often begin an enforcement inquiry with evidence that a competitor saw their product, requested samples, worked with the same vendor, or launched a suspiciously similar item. That evidence may matter to the broader dispute, but access and copying do not automatically prove design patent infringement.
Lanard Toys is a pointed example. The record stated that the accused designer used Lanard’s chalk-pencil product as a reference sample. Even so, the Federal Circuit affirmed summary judgment of design patent noninfringement because the ornamental differences produced a different overall appearance in the context of the prior art. A party can copy unprotected functional or conventional aspects without infringing the claimed design. Conversely, direct evidence of copying is not required if the visual comparison satisfies the ordinary observer test.
The practical lesson is to preserve copying evidence without letting it substitute for claim analysis. The patent drawings, accused product, prior art, and ornamental visual effect remain central.
Can a judge decide infringement without a jury?
Design patent infringement is a question of fact, and the patent owner bears the burden of proving it by a preponderance of the evidence. That does not guarantee a jury trial on every comparison. Summary judgment is available when, after viewing the record in the nonmovant’s favor, no reasonable jury could find infringement.
The recent Range of Motion Products v. Armaid panel opinion affirmed such a result. The patented and accused products shared a broad massager concept, but the panel concluded that the protected design was narrow and that visual differences, considered in context, made the designs plainly dissimilar. The court also concluded that a comparison with the earlier Armaid1 design reinforced noninfringement.
When the Federal Circuit denied rehearing en banc on August 11, 2026, judges debated the “plainly dissimilar” shortcut. The statement supporting denial explained that assessing substantial sameness necessarily involves both similarities and differences, and that summary judgment remains appropriate when no reasonable jury could find infringement. The dissent argued that overuse of the shortcut risks shifting attention from overall similarity to an element-by-element search for differences and removing disputed visual questions from juries.
The denial did not create a new infringement test. It left Egyptian Goddess in place and sharpened a litigation question: whether the comparison is genuinely one-sided or whether reasonable observers could disagree. A party seeking early judgment needs more than a catalog of differences. It needs a record showing how those differences affect the overall ornamental impression, viewed through the relevant prior art.
Build the infringement record around visual proof
For a patent owner, the first task is to confirm ownership, term, and the exact scope of the issued claim. Obtain the accused product in each relevant version, preserve dated photographs and purchase records, and map the claimed views to corresponding views of the product. Collect prior art from prosecution and additional designs that an accused infringer is likely to use as comparison references. Evidence about sales channels and purchaser attention may help identify the proper ordinary-observer perspective.
For an accused infringer, the analysis should begin just as concretely. Identify the ornamental differences that affect the overall appearance, the functional or unclaimed matter that explains broad similarities, and the prior art that narrows the patent’s visual territory. Product-development records may show independent design choices, but independent creation alone is not a defense if the accused design falls within the patent’s scope.
Both sides should avoid relying on cropped images or mismatched viewing angles. Side-by-side exhibits should use comparable perspectives and scale while retaining enough context to show the design as a whole. Physical inspection, high-quality photography, CAD files, sales samples, and expert or survey evidence may be useful depending on the product and disputed issues. The goal is not to make the comparison look favorable through presentation tricks; it is to give the factfinder a reliable visual record.
The filing strategy becomes the enforcement strategy
Design patent litigation often exposes choices made years earlier. Claiming an entire product can preserve a coherent overall design but make it easier for a competitor to avoid the claim by changing prominent portions. Claiming selected portions can target commercially important ornamentation but requires careful broken-line practice and may call for multiple applications or continuations. The drawings must disclose the design clearly enough to support those choices from the start.
Businesses should also coordinate design patents with utility patents, trade dress, copyright, contracts, and marketplace monitoring. Each right protects a different interest and applies a different test. A strong enforcement position usually begins before launch, when the company can still document design development, file appropriate applications, and decide which visual features deserve separate protection.
If a competitor has adopted a similar product appearance, or if a new product needs a filing strategy that will remain useful in enforcement, Tucker Law’s patent litigation practice can evaluate the drawings, accused design, prior art, and procedural options. For matters requiring coordinated federal-court support, review Tucker Law’s intellectual property local counsel services, or contact Tucker Law to discuss the record before positions harden.
