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The PTAB Explores Estoppel in New Representative Decision

The Patent Trial and Appeal Board ("the Board") recently announced the addition of its March 26, 2015 decision in Dell, Inc. et al. v. Electronics and Telecomms. Res. Inst., IPR2015-00549 (“the ‘549 IPR”) to its online list of Representative Orders, Decisions, and Notices.  In this ruling, the Board denies Petitioners’ IPR request under the estoppel provision in 35 U.S.C. § 315(e)(1), which prevents petitioners, real parties-in-interest and privies from challenging an already-adjudicated claim on grounds that were previously raised or could have been previously raised before the Board:

The petitioner in an inter partes review of a claim in a patent under this chapter that results in a final written decision under section 318 (a), or the real party in interest or privy of the petitioner, may not request or maintain a proceeding before the Office with respect to that claim on any ground that the petitioner raised or reasonably could have raised during that inter partes review. (emphasis added)

The Dell decision presents a straightforward application of 35 U.S.C. § 315(e)(1).  In the ‘549 IPR, Dell petitioned for review of U.S. Patent No. 6,978,346 (“the ‘346 Patent”) based on claims 1-9 being obvious under 35 U.S.C. § 103 over the Mylex and Hathorn references.  In its decision, the Board explains that Dell had previously asserted both Mylex and Hathorn against the ‘346 Patent in Dell, Inc. v. Electronics and Telecommunications Research Institute, Case IPR2013-00635 (“the ‘635 IPR”).  Dell’s ‘635 IPR Petition challenged the ‘346 Patent claims on the following grounds: (1) claims 1–3 and 8 as obvious under 35 U.S.C. § 103(a) over Weygant and Mylex (’635 IPR Pet. 20–23); (2) claims 4 and 9 as obvious under 35 U.S.C. § 103(a) over Weygant, Mylex, and Serviceguard5 (’635 IPR Pet. 23–39); (3) claims 5–7 as obvious under 35 U.S.C. § 103(a) over Weygant, Mylex, and ANSI6 (’635 IPR Pet. 39–45); (4) claims 1–3 and 5–8 as anticipated under 35 U.S.C. § 102(b) by Hathorn (’635 IPR Pet. 45–60).  The Board instituted trial in the ‘635 IPR solely on the ground that claims 1-3 and 5-8 were anticipated under 35 U.S.C. § 102 by Hathorn, but ultimately held in its final written decision that these claims were not shown to be unpatentable based on Hathorn.

In comparing the instant ‘549 IPR to Dell’s previous ’635 IPR proceeding, the Board found the patent, challenged claims and asserted prior art to be the same. The only difference, according to the Board, was that the Petitioner combined the prior art in a different combination than previously presented.  Specifically, in the ’635 IPR, Hathorn was asserted as anticipating the claims, whereas in ‘549 IPR, Hathorn was combined with an additional reference, Mylex, which was also previously presented by Dell in the ‘635 IPR.

The Board stated:

On this record, the differences in how the references have been asserted in these proceedings have no weight on our determination of whether the grounds raised in the instant Petition could have been raised in the ‘635 IPR.  Both Mylex and Hathorn were known to Petitioner as prior art to the ‘346 patent, and Mylex has been asserted as an obviousness reference in this Petition and in the ’635 IPR.  It makes no difference to us that Petitioner may have believed Hathorn to be anticipatory reference in the ’635 IPR, and that such a belief may have changed during the trial of the ’635 IPR, where we ultimately determined in our Final Written Decision that Hathorn did not anticipate any claim of the ‘346 Patent.  (‘549 IPR at 5-6).

In other words, not only could Dell have raised the arguments in the prior filing because they relied upon the same prior art references, but it makes no difference to the Board whether or not the arguments were, in fact, raised.

An important limitation of 35 U.S.C. § 315(e)(1) is that estoppel only attaches on a claim-by-claim basis when a final written decision has been rendered by the Board in the IPR proceeding.  35 U.S.C. § 315(e)(1).  The impact of this rule is two-fold.  First, a decision denying institution of review is not a final decision and estoppel therefore does not attach to these decisions.  As a result, additional petitions using the same prior art may still be filed by a petitioner, subject to the provisions set forth in 35 U.S.C. § 315(b) and (d).  Second, estoppel attaches on a claim-by-claim basis.  For example, in the ‘635 IPR, trial was not instituted on claims 4 and 9 of the ‘346 Patent and estoppel thus did not attach to these two claims.  Although Dell was not estopped from review of those claims, the Board denied instituting trial on either claim under 35 U.S.C. § 315(b) for failure to seek review of these claims within one year of Dell being served with a complaint alleging infringement of these claims.

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Kevin C. Amendt is a patent attorney at Mintz. His focus is on strategic intellectual property counseling and litigation. Kevin draws on his strong technical and legal skills to help his clients identify and capture maximum value for their innovations.
Brad M. Scheller is an attorney who handles patent disputes for Mintz clients in industries ranging from electronics and software to consumer goods and cosmetics. He represents clients in federal district courts, in the US Court of Appeals for the Federal Circuit, and at the Patent Trial and Appeal Board.