United States: Evolution Of IPR Estoppel

Inter partes review proceedings ("IPRs") can be powerful weapons in the hands of a petitioner seeking to invalidate potentially threatening patent claims. Since the effective date of the America Invents Act (the "AIA"), petitioners have successfully challenged the validity of 16,688 claims.42

There is, however, a danger of estoppel associated with an unsuccessful challenge that could foreclose a petitioner's future invalidity arguments. Section 315(e) of the patent statute prevents petitioners (or the real parties in interest or the privies of the petitioner) from (1) requesting or maintaining a proceeding before the Patent Office or (2) asserting invalidity in district court or the International Trade Commission with respect to any ground that the petitioner raised or reasonably could have raised during an IPR that resulted in a final written decision.43

However, in the six years since enactment of the AIA, the United States Court of Appeals for the Federal Circuit (the "CAFC"), various district courts, and the Patent Trial and Appeal Board (the "PTAB") have cut back on the strength of the estoppel risk. In Shaw Indus. Grp., Inc. v. Automated Creel Sys., Inc., the CAFC held that an IPR petitioner was not estopped from later raising arguments on grounds that it raised in its petition for IPR, when the PTAB never considered those arguments during the IPR proceeding (post-institution) because the arguments were redundant.44

Central to the CAFC's reasoning was that an IPR does not begin until it is instituted, and the plain language of § 315(e) only creates estoppel for grounds the petitioner raised or reasonably could have raised during the IPR.45

Thus, the petitioner could not have raised—during the IPR—the ground on which the PTAB denied institution. Some district courts have further held that grounds based on publicly available prior art that petitioners could have presented in an IPR, but chose not to, are available in a later proceeding.46

And, now, the PTAB has extended the Shaw rationale, albeit in a somewhat different direction than the district courts' expansion. In Johns Manville Corp. v. Knauf Insulation, Inc., the patent owner filed a motion to terminate based on estoppel, alleging that the current grounds, based on two prior art documents that were actually in the possession of the petitioner at the time of a previous IPR proceeding, "reasonably could have been raised" during that proceeding.47

The petitioner countered that a skilled researcher could not reasonably have been expected to discover the documents from within its own possession prior to the filing of its earlier IPR petition.48

As evidence of its diligence, the petitioner swore that both in-house and outside counsel had conducted nearly thirty employee interviews at the company, but none of those employees possessed the documents.49

And, further, a professional research analyst had conducted a search of internet archives for relevant prior art and did not find the documents in question, apparently because they were never posted online or maintained in electronic form.50

In siding with the petitioner on the estoppel question, the PTAB explained that "[t]he word 'reasonably' is a qualifier that refers to the discretion applied by a qualified searcher in conducting an adequate search."51

The PTAB found that the search conducted was reasonable and rejected the argument that there is a distinction between the petitioner (who was in possession of the documents through its employee) and the lawyers for the petitioner (who were unable to discover those documents in an earlier proceeding).52

It is of note that not everyone thinks that these decisions are a proper reading of § 315(e) or good policy. For example, district courts have criticized the CAFC's holding in Shaw and found a defendant estopped from raising invalidity grounds that it could have presented in its IPR, but chose not to.53

And, one court has classified the CAFC's discussion of IPR estoppel in Shaw as dicta and adopted a narrow reading of Shaw.54

Given the Supreme Court's recent penchant for hearing patent matters, especially where those matters are newsworthy to U.S. tech companies, the estoppel issue will likely be in front of the Court in the near future (unless, of course, the Supreme Court finds IPRs unconstitutional in Oil States).


42 See United States Patent and Trademark Office, Patent Trial and Appeal Board Statistics (Mar. 31, 2017), https://www.uspto.gov/sites/default/files/documents/AIA%20Statistics_March2017.pdf

43 35 U.S.C. § 315(e).

44 817 F.3d 1293, 1300 (Fed. Cir. 2016).

45 Id.

46 See, e.g., Intellectual Ventures I LLC v. Toshiba Corp., Civ. No. 13–453–SLR, 2016 WL 7341713 at *12–13 (D. Del. Dec. 19, 2016); Verinata Health, Inc. v. Ariosa Diagnostics, Inc., Case No. 12-cv-05501-SI, 2017 WL 235048 at *4 (N.D. Cal. Jan. 19, 2017).

47 IPR2016-00130 at 5 (Paper 35) (May 8, 2017).

48 Id.

49 Id. at 6–7.

50 Id. at 7.

51 Id. at 9.

52 Id. at 10.

53 See, e.g., Douglas Dynamics, LLC v. Meyer Prods. LLC, 14-cv-886-jdp, 2017 WL 1382556 at *4–5 (W.D. Wis. Apr. 18, 2017).

54 See Cobalt Boats, LLC v. Sea Ray Boats, Inc., Case No. 2:15-cv-00021 (E.D. Va. June 5, 2017) (D.I. 285) ("The court in Shaw was only making observations in dicta, and it had no occasion to consider restricting estoppel in the manner that other districts have interpreted it.").

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