There is also developing jurisprudence on prior art for design patent infringement, as well as questions such as when are two designs plainly dissimilar, making their way through the courts. But in 2025, the court went back to school, and is poised to decide several more cases, including evaluating the sign design patent illustrated above in Smartrend Mfg. (April 24, 2025) Affirmed grant of motion for summary judgment of non-infringement finding accused design “plainly dissimilar” from patented design without considering prior art. Developing Jurisprudence on Prior Art for Design Patent InfringementDominant Feature from the Prior ArtIn August, the Federal Circuit decided ABC Corp. In design patent infringement analysis, the purpose of comparison prior art is to help inform an ordinary observer’s comparison between the claimed and accused designs.