In re Yamazaki (Fed. Cir. 2012)
Yamazaki filed a terminal disclaimer back in 1996 linking his future Patent No. 6,180,991 to his prior Patent No. 4,581,476. However, after a substantial amendment in the case, Yamazaki filed a petition request to withdraw the terminal disclaimer. As the petitions office has been historically known to do, it took no action on the petition for some time. Meanwhile, the examiner allowed the case, Yamazaki paid the issue fee, and the '991 patent issued in 2001. Since the petition was never decided, the PTO files continued to indicate the presence of a terminal disclaimer. The PTO eventually dismissed the petition based upon its conclusion that a terminal disclaimer cannot be nullified after issuance. The impact is fairly drastic here – with a terminal disclaimer the '991 patent expired in 2003; without a terminal disclaimer the '991 patent would not expire until 2018.
In January 2002 Yamazaki filed a reissue application seeking to fix the terminal disclaimer. Appallingly, the USPTO did not act on the reissue until 2004 (after the prior patent had expired). After an in-person interview in 2005, the examiner agreed in writing that a Reissue application could be used to correct a terminal disclaimer. However, the PTO refused to take any action for two more years and then reversed course. Yamazaki then appealed in 2007 and the BPAI finally issued its decision in 2011. That decision – made by an expanded panel of seven Administrative Patent Judges – held that a Reissue could not be used to remove a terminal disclaimer.
On appeal, the Federal Circuit has affirmed – holding that the plain language of Section 251 coupled with Section 253 prohibit using a reissue to expand a patent's term.
In particular, Section 251 facilitates the correction errors through reissue, but states that once the correction is made USPTO will reissue the patent "for the unexpired part of the term of the original patent." Section 253 indicates that a terminal disclaimer made in writing to the USPTO is "considered as part of the original patent." With these two statutes in hand, the court found that expanding the term by eliminating the terminal disclaimer would contradict the explicit instructions given by the statutory provisions. (Although Section 253 is focused on issued patents, the court held that its interpretation should also apply to pre-issuance disclaimers).
The court paused for a moment to criticize the USPTO delays – calling them puzzling and undeniably unfortunate. However, in the end, those delays do not change the ultimate result.



