Merck Serono S.A. v. Hopewell Pharma Ventures, Inc., Appeal Nos. 2025-1210, -1211 (Fed. Cir. Oct. 30, 2025)

In our Case of the Week, the Federal Circuit upheld a Patent Trial and Appeal Board decision invalidating claims on Merck’s multiple sclerosis drug Mavenclad®, an oral formulation of the compound cladribine.  This precedential opinion is one of two decisions issued last week affirming inter partes review findings on Merck’s claimed cladribine treatments in favor of challengers Hopewell and TWi Pharmaceuticals, Inc.  The Federal Circuit’s opinion in this case turned largely on whether the PTAB’s primary obviousness reference was prior art to Merck’s patents, as the reference pre-dated Merck’s application by less than one year, and Merck contended the disclosure relied on had been the work of at least some of its own inventors.

In affirming the PTAB’s finding that the reference was prior art, the Court examined and clarified its precedent concerning when prior disclosure of an invention is “by others” or “by another” under pre-AIA 35 U.S.C. §§ 102(a) and (e).  Ultimately, the Court reaffirmed the rule of In re Land, 368 F.2d 866 (CCPA 1966), that any difference in the “inventive entity” between the reference disclosure and the challenged claims—whether adding or subtracting inventors—rendered the reference a disclosure “by another” and therefore available as prior art.

Prior to the claimed invention, it was known that cladribine was an effective treatment for MS, although it was primarily administered intravenously or subcutaneously because of the narrow safety margin before the onset of adverse side effects.  In 2002, Merck’s predecessor Serono S.A. had sought to develop oral formulations of cladribine in partnership with another company, IVAX Corp.  In March 2004, IVAX employees Drs. Bodor and Dandiker filed an international patent application (later referred to as “Bodor”) that would later become Hopewell’s primary asserted reference against Merck’s patents.  However, the evidence indicated that the key disclosure in Bodor had been the result of a collaboration between Dandiker, at least three of the four named inventors on Merck’s patents, and others.  (There was an evidentiary question as to whether Merck’s fourth listed inventor, a Dr. de Luca, had meaningfully contributed to this work.)  Serono filed its own patent application underlying Merck’s patents in December 2004, less than a year after the Bodor application was filed.  Serono was acquired by Merck in 2006.

In the case at bar, the PTAB found Merck’s claims obvious over the combination of Bodor and a 1998 reference referred to as Stelmasiak.  Merck contended that the Board erred in finding Bodor to be prior art, arguing that because the disclosure at issue had been invented by at least three of its four named inventors, it was not a disclosure “by others” or “by another” within the meaning of pre-AIA § 102.

The Federal Circuit rejected Merck’s arguments, finding first that there was not a complete identity of “inventive entities” as between the Bodor disclosure and Merck’s patents, at least because Merck had failed to adduce collaborating evidence that Dr. de Luca—later listed on Merck’s patents—provided any inventive contribution to the disclosure at issue in Bodor.  (Because it affirmed the Board’s finding on this point, it declined to reach the question of whether Drs. Bodor and Dandiker had contributed to the disclosure, which may also have defeated the required identity of inventive entities.)  The Court proceeded to review its precedent and affirmed that complete overlap in fact was required for pre-AIA § 102 as set forth in In re Land, rejecting Merck’s argument from intervening precedent that a prior disclosure by a subset of the named inventors would disqualify the reference as prior art.  The Court also rejected Merck’s argument that it had relied on allegedly contrary guidance in the Manual of Patent Examining Procedure, and that it was thus entitled to an opportunity to respond to the Board’s “new” rule under the Administrative Procedure Act.  On this point, the Court pushed back on Merck’s arguments that the MPEP was contrary to Land, and held that because Federal Circuit precedent and not the MPEP controls, Merck in any event had sufficient notice of the governing rule.

Once it confirmed that Bodor was prior art, the Court went on to affirm the Board’s determination that the challenged claims were obvious in view of Bodor and Stelmasiak, rejecting Merck’s contrary factual arguments and upholding the Board’s findings as supported by substantial evidence.

The opinion can be found here.

By Jason A. Wrubleski

ALSO THIS WEEK

Aortic Innovations LLC v. Edwards Lifesciences Corp., Appeal No. 2024-1145 (Fed. Circ. Oct. 27, 2025)

The Federal Circuit reviewed a stipulated judgment of non-infringement following claim construction in a District of Delaware infringement case concerning devices for transcatheter aortic valve replacements. The Court affirmed the district court’s constructions and its judgment as to three of the asserted patents.  Judgment as to a fourth was dismissed for lack of subject matter jurisdiction because the USPTO had issued a certificate cancelling all of the claims asserted in the case.  Accordingly, the Court found “there [was] no actual case or controversy between the parties.”  The Court otherwise affirmed because the district court did not err in construing “outer frame” as necessarily referring to a “self-expanding frame.”  The Court noted that the patent specifications referred to certain structures as an “outer frame” and “self-expanding frame” interchangeably, and that “when a patent repeatedly and consistently characterizes a claim term in a particular way, it is proper to construe the claim term in accordance with that characterization.” A skilled artisan thus would understand the claimed term “outer frame” to be a “self-expanding frame.”  Aortic also presented an alternative argument that Edwards was judicially estopped from arguing its construction, which the Court rejected for not having been presented in the proceedings below.

The opinion can be found here.

By Julia Davis

This article summarizes aspects of the law and does not constitute legal advice. For legal advice with regard to your situation, you should contact an attorney.