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The Use of Broadest Reasonable Interpretation in Inter Partes Review – Evolution of the Law

The U.S. Supreme Court, in Cuozzo Speed Technologies v. Lee,2 is considering the propriety of the U.S. Patent and Trademark Office's ("PTO") rule that, during inter partes review ("IPR"), patent claims receive their "broadest reasonable interpretation" ("BRI").

Briefs in Cuozzo reveal several stakeholder concerns, such as risks of inconsistent results between parallel IPR and district court proceedings under different claim construction standards, and concerns about a patentee's ability to amend claims during IPR. The PTO had argued that its use of BRI was well-established for proceedings involving patents that may be amended. The PTO's actions surrounding Cuozzo indicate that it seeks to (a) understand and balance its stakeholders' interests, and (b) promote certainty in the patent system. In addition, there is a clear need for judicial guidance on the distinctions between BRI and the Phillips standard, employed under Phillips v. AWH Corp.3

The PTO had, even before the Federal Circuit's Cuozzo decision, undertaken a "nationwide listening tour" that revealed frustration with amendment practice during IPR. In response, the PTO issued rules in May 2015 that relaxed page limitations for motions to amend, and allowed for an appendix of proposed substitute claims that did not count toward final page limit.5

After the Federal Circuit's decision, the PTO proposed additional rules that, while maintaining the BRI standard during IPR, would allow a Phillips-type construction to apply for patents expiring before a final IPR decision.6 Regarding amendments, the PTO noted that patentees may propose multiple replacements for each claim canceled in amendment, suggesting a willingness to entertain alternative proposals during IPR.7 Rules issued in April 20168 apply the BRI standard during IPR, but also allow parties to request a Phillips-type construction for patents expiring within 18 months of entry of the Notice of Filing Date Accorded to Petition.9 The impact of these rules is yet unclear, and at present the ability to amend claims remains limited, as shown by recent reports that the Patent Trials and Appeal Board ("PTAB") has only granted 6 of 146 motions to amend using substitute claims.10

The PTO has also provided guidance on IPR practice through interpretive decisions. For example, in MasterImage 3D v. ReadD Inc.11 the PTAB clarified previous statements in Idle Free Systems v. Bergstrom12 (which had been criticized as suggesting that patentees might have to search for and submit all possible prior art when moving to amend) explaining that IdleFree merely referred to the prior art that a patentee submits under existing duties of candor. The PTO recently designated MasterImage 3D as precedential, cementing its clarification on IPR amendment practice.

In addition to the PTO's guidance on IPR practice, recent Federal Circuit decisions regarding IPRs address the "broadest reasonable interpretation" standard versus a Phillips-type standard. In Microsoft Corp. v. Proxyconn, Inc.,13 the Federal Circuit found that the PTAB's construction was improper even under BRI, because it subsumed discrete claim elements. The court emphasized that even under BRI, a "construction 'cannot be divorced from the specification and the record evidence, and must be consistent with the one that those skilled in the art would reach."14

In Straight Path IP,15 the Federal Circuit noted that, even though the PTAB should have applied Phillips¸ not the BRI standard, for a patent that expired during IPR,16 the PTAB's construction was incorrect even under BRI. The court explained that where a claim's plain and ordinary meaning is clear, the specification is less important to claim interpretation, and that absent a clear disavowal or disclaimer, the specification cannot override a claim's plain and ordinary meaning.17 On remand, the PTAB applied the Federal Circuit's construction, upholding the claims it previously invalidated.18 Similarly, the Federal Circuit held in Black & Decker, Inc.19 that while the PTAB improperly adopted a construction under BRI in lieu of a Phillips-type analysis, the PTAB's construction remained correct under Phillips.20 While in some cases the particular claim construction standard was considered outcome-determinative,21 further guidance is still needed on how these standards differ in practice.


  1. The authors are Partner and Associate, respectively, at Paul, Weiss, Rifkind, Wharton & Garrison LLP.
  2. On appeal from the Federal Circuit's July 8, 2015 decision In re Cuozzo Speed Techs., LLC, 778 F.3d 1271 (Fed. Cir. 2015), opinion substituted in 793 F.3d 1268 (Fed. Cir. 2015), cert granted in 136 S. Ct. 890 (2016).
  3. 415 F.3d 1303 (Fed. Cir. 2005).
  4. See 80 Fed. Reg. 28,561, 28,561 (May 19, 2015).
  5. Id. at 28,562 (to be codified at 37 C.F.R. pts. 42.24(a), 42.121(b), and 42.221(b)).
  6. See 80 Fed. Reg. 50,720, 50,722 (Aug. 20, 2015).
  7. See id. at 50,722–23.
  8. Effective May 2, 2016.
  9. See 81 Fed. Reg. 18,750, 18766 (Apr. 1, 2016) (to be codified at 37 C.F.R. pt. 42).
  10. See http://www.law360.com/ip/articles/792757/ipr-motions-to-amend-rays-of-hope-despite-gloomy-stats.
  11. MasterImage 3D, Inc. v. RealD Inc., Case IPR2015–00040 (PTAB July 15, 2015) (Paper 42).
  12. Idle Free Systems, Inc. v. Bergstrom, Inc., Case IPR2012–00027 (PTAB June 11, 2013) (Paper 26).
  13. 789 F.3d 1292 (Fed. Cir. 2015).
  14. Id. at 1298 (internal quotations and citations omitted); see also Dell Inc. v. Acceleron, LLC, 2016 U.S. App. LEXIS 4686, * 13–14 (Fed. Cir. 2015) (noting that PTAB's construction under BRI was inconsistent with plain claim language, and conflicted with the specification).
  15. Straight Path IP Group, Inc. v. Sipnet EU S.R.O., 806 F.3d 1356 (Fed. Cir. 2015).
  16. Id. at 1360.
  17. Id. at 1361–63.
  18. See Sipnet EU R.S.O. v. Straight Path IP Group, Inc., Case IPR2013-00246 (PTAB May 23, 2016) (Paper 73) at 6, 15–17.
  19. Black & Decker, Inc. v. Positec USA, Inc., 2016 U.S. App. LEXIS 9039 (Fed. Cir. 2016).
  20. Id. at * 10-11.
  21. See PPC Broadband, Inc. v. Corning Optical Commc'ns RF, LLC, 815 F.3d 734, 741–43 (Fed. Cir. 2016) (noting that for specific claim under review, proper construction under Phillips-type analysis would be narrower than under BRI standard).