Once belittled as "poor man's litigation," reexamination is now a hot defense tactic in patent infringement cases. Requests to the Patent and Trademark Office for reexaminations related to litigation have nearly tripled, from 116 in 2003 to 450 last year, according to the PTO. (The comparable figure for the first half of 2008 dipped 12 percent, but there might actually be no slowdown-lawyers often lag in identifying which reexam requests are related to litigation, says a PTO spokesperson, and total reexam requests continue to climb.) More than 90 percent of the requests for reexam are approved. Teresa Corbin, a partner in Howrey's San Francisco office, says: "In just about every case, it's now a serious consideration whether or not to bring a reexamination."
Reexaminations were intended to provide an inexpensive reality check on the validity of "doubtful patents," in the words of the patent law amendments of 1980. But the ex parte procedure thus created did not take off in a big way because it limits a third-party challenger to just an initial role in contesting a patent's validity. An inter partes alternative, which Congress enacted in 1999 as a spur to reexams, permits a patent challenger's response at each of the several stages in the PTO's deliberations.
But the reexamination procedure still didn't catch on because of the PTO's policy of assigning cases to the same examiner who had originally issued the patent. That policy was abandoned in 2000, but patents were nonetheless reexamined by the same department where they had been issued and where a bias to uphold the earlier decision might presumably have prevailed.
Then, to assuage many litigators' worries about partiality, in 2005 the PTO established the Central Reexamination Unit, a separate corps of senior examiners to conduct all the reexams. Because the 1999 law covers only patents applied for after November 29, 1999-and because it typically takes almost three years of review before the PTO issues a patent-it's only recently patents have emerged that are subject to the inter partes option. But lately requests have been skyrocketing: In 2004 there were five requests for inter partes proceedings related to litigation; in 2007 the number was 81.
The results so far indicate that the inter partes proceeding delivers a more powerful blow against patent holders, though some lawyers caution that the sample is still too small to be conclusive. As of last year, the PTO had completed only 17 inter partes reexaminations with these results: 13 patents canceled, or a whopping 76 percent; three in which some patent claims were changed, or 18 percent; and just one confirmed, or 6 percent. The comparable ex parte figures (for the period 1981 to 2007): just 13 percent canceled; some claims changed, 59 percent; all claims confirmed in 28 percent. But going the inter partes route carries a big risk: issues that could have been raised with the PTO can not be later raised in court.
