Terminal Disclaimer Permanent Once Patent Issues
Back in January of 2011 I discussed the appeal decision in Ex parte Shunpei Yamazaki relative to patent reissue
practice. In Yamazaki,
a reissue patent application was filed shortly after issuance of U.S. Patent 6,180,991 for the purpose of withdrawing an earlier filed terminal disclaimer.
By way of background, the '991 patent issued on January 30, 2001 (based upon an application filed April 21, 1995). During the original prosecution, a terminal disclaimer was filed (November of 1996) to overcome a double patenting rejection. Thereafter, the claims subject to the earlier double patenting rejections were amended. Since the amended claims were believed to be distinct from those of the earlier patent, the Applicant petitioned to withdraw the earlier filed terminal disclaimer (April 1999). The petition remained pending for some 20+ months at the USPTO, but, the patent issued prior to any USPTO action on the petition filing. The petition was ultimately dismissed as moot once the '991 Patent issued.
Adding insult to injury, the USPTO explained in their belated petition decision that a terminal disclaimer could not be removed once a patent issues as patent reissue did not contemplate such mistakes as "error" under the reissue statute. In other words, even though the patent holder had disclaimed some 14 years of patent term by mistake, there was no mechanism to cure that mistake post issuance. Nevertheless, the Patentee filed a patent reissue application in an attempt to withdraw the terminal disclaimer.
In deciding the propriety of a patent reissue proceeding to remove a terminal disclaimer, an expanded panel of the BPAI (now PTAB) held that patent reissue could not reset the term of the original patent (which was set by the disclaimer). Interestingly, the BPAI decision also included concurring opinions that would have held differently had the patent not expired prior to completion of the reissue proceeding (December 2003).
Last week, the CAFC affirmed the USPTO, and made clear that patent reissue cannot withdraw a terminal disclaimer, even if the reissue proceeding were capable of concluding prior to expiration.