Claims denied entry during prosecution for including new matter may prevent other claims from being later interpreted to encompass the same subject matter. Here, for example, claims directed to a particular species of cytotoxin that were rejected during prosecution for lack of enablement effectively barred otherwise generic terminology in other claims from being construed as including that species. “Although 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a patent applicant cannot later obtain scope that was requested during prosecution, rejected by the Examiner, and then withdrawn by the applicant.” It may therefore be best to ardently contest new matter rejections during prosecution rather than simply canceling those claims.
Background / Facts: The patent being asserted here describes and claims a monoclonal antibody that binds a defined human cytotoxin. The claims as originally filed described the antibody as a “monoclonal antibody,” but during a lengthy prosecution the patentee first limited all the claims to murine (mouse) antibodies, and then sought to remove this limitation with new and broader claims. The examiner rejected the proposed claims on the ground of new matter not supported in the specification. The patentee then withdrew the proposed specific claims, and the application was passed to issuance.
Issue(s): Whether the monoclonal antibody of claim 1 is limited to murine (mouse) monoclonal antibodies.
Holding(s): Yes. “We agree that the prosecution history requires this construction, for the scope now sought by [the patentee] was requested of the Examiner, and refused on the ground of new matter. … [The patentee] argues that absent a narrowing amendment to the proposed claim that is now claim 1, there can be no prosecution estoppel to the scope of claim 1, merely because some proposed different claims were rejected by the examiner and then dropped by the applicant. That is not a correct general principle. Although 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a patent applicant cannot later obtain scope that was requested during prosecution, rejected by the Examiner, and then withdrawn by the applicant.”