On September 08, 2016, in UCB, Inc. v. Yeda Research and Development Co., the Federal Circuit affirmed the determination by the District Court for the Eastern District of Virginia that UCB's Cimzia® brand antibody does not infringe Yeda's U.S. Patent No. 6,090,923. In affirming the District Court's grant of summary judgment of non-infringement, the Federal Circuit concluded that Yeda was estopped from including chimeric and humanized antibodies within the scope of the monoclonal antibodies claimed in the '923 patent.
The '923 patent is directed to a monoclonal antibody that binds a defined human cytotoxin. Claim 1 is representative:
1. A monoclonal antibody which specifically binds a human cytotoxin having a molecular weight of about 17,500 as determined by polyacrylamide gel electrophoresis, said cytotoxin being obtainable from stimulated human monocytes, said cytotoxin being further characterized by exhibiting a cytotoxic effect on cycloheximide-sensitized SV-80 cells and by being obtainable in a state of enhanced purity by adsorption of the cytotoxin from an impure preparation onto controlled pore glass beads, and subsequent desorption of the cytotoxin in a state of enhanced purity.
UCB filed suit against Yeda, seeking a declaration that its Cimzia® brand antibody does not infringe the '923 patent and a declaration that the '923 patent is invalid. Yeda counterclaimed for infringement. In support of its claim of infringement, Yeda argued that the claims of the '923 priority application should be construed to cover chimeric antibodies since chimeric monoclonal antibodies were known at the time the '923 priority application was filed. UCB, however, argued that the prosecution history of the '923 patent prohibited coverage of chimeric antibodies.
During prosecution of the '923 patent, Yeda had argued that the term "monoclonal antibody" should encompass chimeric monoclonal antibodies, stating that "[w]e do not believe that the term necessitates that the monoclonal antibody be produced by the original hybridoma cell; the term should encompass chimeric monoclonal antibodies produced by a genetically engineered cell line," and noting that "Applicants are particularly interested in protecting chimeric forms of their anti-cytotoxin mouse monoclonal antibodies." In support of its argument, Yeda filed a Declaration from Dr. Hartmut Engelmann, in which Dr. Engelmann cited two references that preceded the effective filing date of the '923 priority application and described mouse-human chimeric antibodies. Yeda also presented new claims 45-48, which were directed to "rat, hamster and human antibodies and chimeras thereof" and to "chimeras of" mouse monoclonal antibodies. The Examiner rejected the new claims for adding new matter, and Yeda cancelled all of the claims reciting chimeric antibodies. Claim 41, which issued as claim 1 in the '923 patent, did not mention chimeric antibodies and had not been amended during prosecution to recite chimeric antibodies.
At trial, the District Court construed "monoclonal antibody," as used in the claims of the '923 patent, to mean "a homogenous population of a single type of antibody produced via hybridoma and not including chimeric or humanized antibodies." In view of this construction, the District Court granted summary judgment of non-infringement to UCB, determining that the prosecution history of the '923 patent prohibited construction of claim 1 to cover humanized and mouse-human chimeric antibodies.
On appeal, Yeda argued that claim 1 had never been rejected on the ground of new matter, and that only the specific species claims (i.e., claims 45-48) had been rejected by the Examiner for containing new matter. Yeda also argued that claim 1 does not recite any particular monoclonal antibody or species of chimera, and that the claim should not be limited to the examples in the specification. While acknowledging that "Yeda is correct in that generic terms in claims are construed in light of that which is already known," the Federal Circuit noted that "the content of the specification and actions and arguments during prosecution must also be considered, in defining the scope of a generic term in a claim," and cited Advance Transformer Co. v. Levinson, 837 F.2d 1081, 1083 (Fed. Cir. 1988), for the proposition that "[p]ositions taken in order to obtain allowance of an applicant's claims are pertinent to an understanding and interpretation of the claims that are granted by the PTO . . . and may work an estoppel as against a subsequent different or broader interpretation." The Court explained that (citations omitted):
During prosecution, Yeda submitted new claims specific to "rat, hamster and human antibodies and chimeras thereof" as well as claims specifically encompassing "chimeras of" mouse monoclonal antibodies and "nonmurine" monoclonal antibodies. Yeda argued that its invention is not limited to murine antibodies to human cytotoxin, and "should encompass chimeric monoclonal antibodies produced by a genetically engineered cell line." The Examiner rejected the proposed claims on the ground of new matter not supported in the specification. Yeda then withdrew the proposed specific claims, and the application was passed to issuance. The district court held that Yeda cannot now obtain a claim construction that recovers claim scope that was yielded in order to obtain issuance of the patent, and construed the claims as excluding chimeric and humanized antibodies.
In response to Yeda's argument that there could be no prosecution estoppel with respect to the scope of claim 1 absent a narrowing amendment to the claim 1, the Court noted that this "is not a correct general principle," stating that "[a]lthough each claim in a patent warrants independent consideration in light of its particular facts and history, the general rule is that a patent applicant cannot later obtain scope that was requested during prosecution, rejected by the Examiner, and then withdrawn by the applicant." The Federal Circuit determined that "[s]uch estoppel was reasonably applied to claim 1 by the district court, although claim 1 had not been amended," and therefore affirmed the District Court's holding that Yeda was estopped from including chimeric and humanized antibodies within the scope of the monoclonal antibodies claimed in the '923 patent.
UCB, Inc. v. Yeda Research and Development Co. (Fed. Cir. 2016)
Panel: Circuit Judges Newman, Lourie, and Chen
Opinion by Circuit Judge Newman
