Claims in Reissue Patent Must Match Original Patent Requirements

Written June 20, 2019

The Federal Circuit on June 17, 2019, held that patent holders who introduce new claims during the prosecution of a patent must ensure those claims meet the requirements in the original patent. Forum US, Inc. v. Flow Valve, LLC, Fed. Cir., No. 18-01765.

Flow Valve appealed a summary judgment by the district court invalidating US Patent No. RE45,878, which relates to fixtures used to hold workpieces during machining. The patent is a reissue of US No. 8,215,213, which required fixtures with arbors for holding oil and pipe gas fittings.

Forum US Inc. argued in its summary judgment motion that Flow Valve’s reissue claims improperly broadened the claims of the original patent because arbor limitations were omitted. The original patent didn’t disclose an invention without arbors, which, they argued, violated Section 251.

The Federal Circuit agreed, saying that the reissue claims “do not comply with the original patent requirement of 35 U.S.C. § 251 as a matter of law[.]”