- within Compliance topic(s)
In Smartrend Manufacturing Group (SMG), Inc. v. Opti-Luxx Inc., the Federal Circuit vacated a finding of design patent infringement due to an erroneous claim construction. The panel also reversed the district court's denial of JMOL on infringement under the doctrine of equivalents (DOE), finding the accused products failed to perform a function required by the asserted utility patent.
Background
Smartrend Manufacturing Group (SMG) sued Opti-Luxx for allegedly infringing a design patent and a utility patent, which cover illuminated school bus signs. The district court ruled in favor of SMG on both patents, denied Opti-Luxx's motion for JMOL, and entered a permanent injunction against Opti-Luxx. Opti-Luxx appealed, challenging the district court's claim construction for the design patent and the finding of infringement under the doctrine of equivalence for the utility patent.
Issues
- Whether the district court erred in construing the design patent's "transparency" description; and
- Whether the accused products infringed the utility patent under the doctrine of equivalents.
Holdings
- The panel held the district court improperly broadened "transparency" to encompass both transparent and translucent features.
- The panel reversed the DOE infringement judgment, finding that no reasonable jury could conclude Opti-Luxx's integrated frame performed the same functions as the claimed separate frame.
Reasoning
First, in reviewing the design patent's claim construction, the Federal Circuit stressed that when a design is claimed "as shown and described," as was the design patent at issue, the patent's scope is limited by both the drawings and the accompanying written description. Here, SMG's description stated that "oblique shading lines visible in the front and perspective views denote transparency." Despite this clear limitation, the district court broadened the meaning of "transparency" to also include "translucency." The Federal Circuit found this interpretation improper, holding that both the claims and specification restrict the term to truly transparent features—not translucent ones. The panel further cautioned that expert testimony cannot be used to expand or override the plain and ordinary meaning of a claim term unless it is backed by reliable, objective extrinsic evidence.
Second, the Federal Circuit evaluated infringement under the doctrine of equivalents by applying the function-way-result test. The panel determined the patent specification clearly described the function of the "frame" as being "configured to removably receive the sign." The panel found that Opti-Luxx's accused product, which featured an integrated frame, could not perform this essential function. Notably, SMG's own expert conceded the accused product lacked this capability. Based on this undisputed evidence, the Federal Circuit reversed the finding of infringement, concluding the accused product did not perform the claimed functions.
Conclusion
The Federal Circuit's decision underscores the importance of adhering closely to the intrinsic evidence when construing patent claims—particularly in design patents where the description and illustrations explicitly define scope. The ruling also reinforces that, under the doctrine of equivalents, infringement cannot be found if the accused product does not perform all functions required by the patent claims.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
