It has become a fairly common practice for a single petitioner to file more than one IPR against a single patent.  To date, approximately 200 patents have been the subject of multiple IPRs filed by a single petitioner.  Some of these patents have been the subject of multiple IPRs filed by multiple petitioners.  For example, U.S. Patent No. 6,805,779 to Chistyakov has been the subject of two or more IPRs filed against it by Fujitsu Semiconductor Limited (filed three), GlobalFoundries US, Inc. (filed two), Intel Corporation (filed five), Taiwan Semiconductor Manufacturing Company, Ltd. (filed three), The Gillette Company (filed five), and Toshiba Corporation (filed three). 

Petitioners have often divided the multiple IPRs based on groupings of claims.  For example, in two IPRs filed by Corning Incorporated against U.S. Patent No. 6,298,189 to Szum, Corning focused on claims 1-52 of the ‘189 Patent in one of the IPRs (IPR2013-00048) and claims 53-66 in the other IPR (IPR2013-00049).  Veeam Software Corporation took the same approach against U.S. Patent No. 6,931,558 to Jeffe.  In IPR2013-00141, Veeam challenged claims 1-15 of the ‘558 Patent and in IPR2013-00142 it challenged claims 16-23.  One advantage of such an approach is to circumvent the page limit requirements imposed by 37 C.F.R § 42.24, which limits the number of pages of a petition requesting an IPR to 60 pages as well as other filings during the IPR proceeding.  In the three petitions it filed against the ‘779 Patent, for example, Fujitsu Semiconductor Limited used a total of 180 pages or three times the 60 page limit for a single IPR.  See IPR2014-918; IPR2014-856 and IPR2014-859.

Another approach petitioners have used when filing multiple IPRs against a single patent is to do so based on arguments.  Such an approach was taken by Dell Inc. against U.S. Patent 6,948,021 to Derrico.  In one IPR, Dell took the position that claims 1–4, 6–19, 30, and 34–36 of the ‘021 patent were unpatentable in view of U.S. Patent Nos. 7,032,119 and 6,950,895 (see IPR2013-00443) and, in a second IPR, Dell took the position that claims 1–4, 6–20, 22–24, 30 and 34–36 of the ‘021 patent were unpatentable in view of U.S. Patent No. 6,757,748 (see IPR2013-00440).  This approach also advantageously circumvents the page limit requirements imposed by 37 C.F.R § 42.24.  In addition, by using this approach, petitioners are less likely to have proposed grounds of rejection denied by the PTAB based on redundancy.

Thus, petitioners have effectively circumvented the page limit requirements imposed by 37 C.F.R § 42.24 and have advanced grounds of rejections that otherwise would have been denied by the PTAB as being redundant by filing multiple IPRs against a single patent.