Smartrend Mfg. Grp. (SMG), Inc. v. Opti-Luxx Inc
Authored by: Jeremy J. Gustrowsky
In a recent decision, the Federal Circuit addressed important issues of claim construction and patent infringement in Smartrend Mfg. Grp. (SMG), Inc. v. Opti-Luxx Inc. The case involved two patents related to illuminated school bus signs: U.S. Design Patent No. D932,930 (the “D930 patent”) and U.S. Patent No. 11,348,491 (the “‘491 patent”). After a jury found that Opti-Luxx’s school bus sign infringed both patents, the Federal Circuit reversed in part, vacated in part, and remanded the case for further proceedings.
A key issue in the case was the meaning of “transparency” in the D930 design patent. The district court had interpreted “transparency” to include both “transparent” and “translucent,” but the Federal Circuit disagreed. The appellate court held that the patent’s description expressly limited the scope to “transparency” only, excluding “translucency.” This means that only surfaces that are truly transparent, not merely translucent, are covered by the D930 patent. As a result, the court vacated the infringement finding for the D930 patent and ordered a new trial with the correct claim construction.
For the ‘491 utility patent, the court focused on whether Opti-Luxx’s integrated frame could infringe under the doctrine of equivalents. The patent required a frame that was “separate and distinct” from the sign, allowing for easy replacement or customization of the sign panel. Opti-Luxx’s product had an integrated frame that could not be separated, and Smartrend’s own expert admitted it could not perform the functions described in the patent. The Federal Circuit concluded that no reasonable jury could find infringement under the doctrine of equivalents and reversed the judgment of infringement for the ‘491 patent.
This decision underscores the importance of precise claim language and the limits of broadening patent protection through claim construction or the doctrine of equivalents. Patent owners and accused infringers alike should carefully consider how courts interpret both the literal and functional scope of patent claims.