Federal Circuit Clarifies That Only Identical Inventors Avoid Becoming Prior Art Under Pre-AIA 102(e)

In Merck Serono S.A. v. Hopewell Pharma Ventures, Inc., No. 25-1210 (Fed. Cir. Oct. 30, 2025), the Federal Circuit affirmed a PTAB decision invalidating two Merck patents directed to methods for treating multiple sclerosis, U.S. Patent Nos. 7,713,947 and 8,377,903.

Hopewell filed IPR petitions challenging claims of both of Merck’s asserted patents as obvious over Bodor in view of Stelmasiak. Merck argued that the Bodor reference, which was published two months before the priority date of Merck’s applications, was not prior art because De Luca, one of the inventors of the asserted patents, had made an inventive contribution to the Bodor application, despite not being listed as an inventor. The PTAB disagreed, finding (1) that Merck failed to produce sufficient evidence of De Luca’s contribution, and (2) that Bodor would nonetheless qualify as prior art.

On appeal, the Federal Circuit affirmed, explaining that whether a reference is “by another”—and thus disqualified as prior art under pre-AIA 102(e)—is based on whether the references are by the same inventive entity. That is, the inventors in the prior art reference must be exactly the same as those in the relevant patent for the reference to be excluded as prior art. The Court cited In re Land, 368 F.2d 866, 877 (CCPA 1966), which explained that “an invention made jointly by A & B cannot be the sole invention of A or B and vice versa.” Because Merck failed to provide sufficient evidence of De Luca’s contribution to Bodor, the Federal Circuit affirmed.