In re Yamazaki

Once a patent has issued subject to the terms of a terminal disclaimer, the Patent and Trademark Office is foreclosed from later reissuing the patent with a term greater than that for which the patent was originally issued.

Opinion (Lourie): Yamazaki applied for a patent related to a new semiconductor. Following an initial rejection, because the proposed patent covered claims found in a prior patent issued to Yamazaki, Yamazaki filed a terminal disclaimer agreeing to forego any term for the new patent that would exceed the time period covered by the prior patent. Later, Yamazaki amended each claim in the application and petitioned to withdraw the terminal disclaimer. The Patent Office, however, did not act on the petition and issued the new patent with a term that expired on the same date as the prior patent. Later, the Patent Office dismissed the withdrawal petition, concluding that the terminal disclaimer could not be nullified after the patent had been issued. Yamazaki then requested that the patent be reissued without the constraint of the terminal disclaimer. The Patent Office refused to reissue the patent, and Yamazaki appealed to the Board, which denied the request. Yamakazi then appealed to the Federal Circuit. The Court of Appeals held that a disclaimer filed before a patent issued should create the same result because by filing the disclaimer, the patentee agreed to forgo the disclaimed portion of the patent and the shortened term became a part of the patent as though the disclaimer had never been filled. Once the patent issued subject to the agreement contained in the disclaimer, therefore, the Patent Office was foreclosed from later reissuing the patent with a term greater than what had originally been issued. Accordingly, the Federal Circuit AFFIRMED the decision of the Board.