Provisional Discretion: CAFC’s Repeat Performance in Affirming Prosecution History Disclaimers

5.6.25

DNA Genotek Inc. v. Spectrum Sols. LLC, No. 23-2017 (Fed. Cir. Feb. 14, 2025

On February 14, 2025 the US Court of Appeals for the Federal Circuit (“CAFC”) again invoked prosecution history disclaimer from a provisional-to-nonprovisional transition to limit the scope of claims to exclude subject matter not explicitly recited from the provisional in the nonprovisional. This disclaimer persists even where the nonprovisional incorporates the provisional by reference.

In DNA GenoTek, Inc. v. Spectrum Solutions LLC, No. 23-2017, the court addressed claim construction concerning a patent for a device that preserves nucleic acids in biological samples. The patent, U.S. Patent No. 10,619,187, includes claims describing a “reagent compartment” of the containment vessel in the device. The central issue on appeal was whether the district court’s construction of this term as a “region or section of the containment vessel” improperly excluded a reagent compartment in a cap, which the Federal Circuit ultimately affirmed.

The dispute arose from the district court’s summary judgment in favor of Spectrum Solutions, asserting that Spectrum’s product did not infringe the ’187 patent based on the construed definition of “reagent compartment” as a part of the containment vessel. GenoTek challenged this interpretation, arguing that the district court wrongfully imported limitations from specific embodiments described in the patent. However, the Federal Circuit found that the patent’s specification itself supported the lower court’s interpretation, explicitly stating that the “reagent compartment” is located within the containment vessel. This finding was underscored by consistent descriptions in both the summary of the invention section and the detailed description of the patent.

Further influencing the court’s decision was the patent’s prosecution history. Notably, GenoTek had removed embodiments directed to a reagent compartment in the cap from its provisional application when filing the non-provisional. This amendment evidently indicated a clear intent to restrict the reagent compartment’s location to within the containment vessel—a principle upheld in previous decisions such as DDR Holdings v. Priceline regarding prosecution history estoppel.

Moreover, during an inter partes review (IPR) of another patent, GenoTek’s counsel differentiated the ’187 patent from other designs by highlighting the unique placement of its reagent compartment. These comments reinforced the interpretation that the compartment was meant to be within the container, not the lid. Thus, the Federal Circuit affirmed the district court’s findings, supporting the claim construction and confirming the non-infringement ruling, and demonstrating how intrinsic and extrinsic evidence can guide patent claim interpretations in litigation.

Sam Raque | Associate Attorney