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Strategies for Avoiding Decisions Denying Institution on Redundancy Grounds

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I. Introduction

Inter Partes Reviews (IPRs) continue to be a popular tool for challenging the post-grant validity of a patent.1 When filing IPR petitions, Petitioners can, and often do, wish to present multiple grounds of rejection for the Patent Trial and Appeal Board (PTAB) to consider. The Federal Regulations, however, give the PTAB broad discretion to institute on some asserted grounds but not others. 37 C.F.R. § 42.108(a) (“the Board may authorize the review to proceed. . . on all or some of the grounds of unpatentability asserted for each claim”). This authority has been recognized with approval by the Federal Circuit.2 The Federal Circuit has held that the PTAB has non-appealable institutional discretion to choose which grounds of a petition to institute or deny, and that discretion may include denial of grounds that the PTAB views as “redundant.”3

On the one hand, a finding of “redundancy” may have an upside. In 2016, the Federal Circuit held in Shaw Industries Group v. Automated Creed Systems that the PTAB’s denial of a ground as “redundant” cannot result in estoppel because it was not and could not have been raised “during” the IPR.4 The fact that estoppel does not attach to grounds not instituted for redundancy reasons may raise possibilities for strategically presenting redundant grounds during an IPR.5

On the other hand, however, some Petitioners may have strategic reasons for wanting institution on all proposed grounds regardless of estoppel considerations. For example, faced with uncertainty with how the PTAB will view the relative strengths of the grounds or how the Patent Owner will present its validity arguments, the Petitioner may wish to have multiple grounds to avoid having all of its eggs in one invalidity basket. In those circumstances, Petitioners might seek to avoid a decision denying institution on “redundancy” grounds. Petitioner’s potential desire for institution on multiple grounds, however, can be contrasted against the PTAB’s charge to take into account “the efficient administration of the Office” and “the ability of the Office to timely complete [instituted] proceedings” (35 U.S.C. § 316(b)), as well as the regulatory provisions that mandate these proceedings be “construed to secure the just, speedy, and inexpensive resolution of every proceeding” (37 C.F.R. § 42.1(b)).6 Inevitably, those Petitioners that present multiple grounds will face arguments from the Patent Owner that those grounds are redundant. The Patent Owner’s preliminary response is likely to argue institution on multiple grounds is an inefficient waste of the PTAB’s limited resources. These arguments may be appealing to the PTAB, particularly in view of the continuing rise in PTAB filings and the recent Federal government hiring freeze.7

The PTAB has made it clear that to avoid a finding of redundancy on multiple grounds the Petitioner should identify the “relative strengths or weaknesses in the prior art disclosures as they relate to the limitations of the claims.”8 “[I]n the absence of the Petitioner identifying meaningful distinctions in terms of relative strengths and weaknesses of the different prior art references, it is within the discretion of the Board to conclude that even with different facts in different grounds, multiple grounds may nevertheless be redundant”9

Petitioners seeking institution on multiple grounds may consider setting forth persuasive reasons why those multiple grounds are not redundant. In order to avoid a finding of redundancy, Petitioners have used various strategies to varying degrees of success for presenting those reasons. This article discusses several such strategies and how the PTAB has viewed those arguments.

II. Circumstances Where the PTAB has Rejected Multiple Grounds As Redundant

One option some Petitioners have chosen is to provide no reasons at all for why the Board should not view multiple grounds as redundant. While there is a possibility that the PTAB may exercise its discretion to institute on multiple grounds anyway,10 such Petitioners risk a finding of redundancy at their peril (particularly if the Patent Owner presents persuasive arguments that the grounds are indeed redundant). Such a strategy may be considered, for example, by Petitioners who a) may not want to be forced to explain the relative strengths and weaknesses of the multiple grounds for strategic reasons, and b) can otherwise live with a finding of redundancy in view of the Federal Circuit’s narrow application of estoppel as articulated by Shaw and its progeny.11

Some Petitioners have gone one step further and have enumerated some differences between the grounds but stopped short of commenting on how those differences affect the relative strengths and weaknesses of the grounds. For example, in Apple Inc. v. Parthenon Unified Mem. Arch. LLC, Apple argued that the various grounds “address the [claim limitations] in different ways” and that the differences in the disclosures “affects the mapping to the claimed elements.”12 The PTAB found these reasons insufficient to avoid redundancy and noted in its decision that Apple had failed to “argue that these ‘differences’ render one set of grounds superior to the other,” and that “the mere presence of differences is not a sufficient reason to prefer one ground over another or to institute an inter partes review on multiple grounds of essentially the same scope.”13

Another strategy that has been tried is to suggest that the multiple grounds are presented in the alternative. For example, in Micron Tech. v. Innovative Mem. Sys., the Petitioner presented a second grounds as an alternative “if the Board finds that [the primary ground] does not disclose a method for compensating for floating-gate coupling during programming.”14 The PTAB, however, found (in its institution decision) that the primary reference did adequately disclose the method and therefore declined to institute on the second ground.15 Petitioners wishing to avoid redundancy findings may consider avoiding expressing the multiple grounds as merely alternatives based on the PTAB’s finding. The PTAB may not wait to make such findings until the final written decision and may instead decide to deny institution on an alternative ground as redundant in its initial determination.

III. Strategies that Have Led to Institution Decisions on Multiple Grounds

Petitioners have used various strategies for convincing the PTAB that there is a lack of redundancy between the proposed grounds. The most straightforward strategy is to simply present a straightforward argument explicitly setting forth the strengths and weaknesses of various limitations. For example, on the one hand, Ground 1 may be subject to attack on Element A, but Ground 2 may provide strong disclosure for Element A. On the other hand, Ground 2 may be subject to attack on Element B, but Ground 1 may be strong on Element B. Petitioners, however, may have strategic reasons for not wishing to provide a roadmap of the weaknesses in its proposed grounds to the PTAB and the Patent Owner.

Petitioners are therefore finding other creative ways to present persuasive reasons why the multiple grounds are not redundant. For example, in the scenario above, one way to frame the issues in a way that is not critical to the Petitioner’s own proposed grounds would be to suggest that the grounds are not redundant at least because the Petitioner expects the Patent Owner to make different validity arguments for each ground. The downside to this approach is that it may nevertheless give the Patent Owner somewhat of a roadmap of arguments to make (or arguments to avoid) and may further incentivize the Patent Owner to find a single common reason for denying institution of both grounds.

Another strategy that has been used with success is to argue that multiple grounds are presented because the Patent Owner has made or may take divergent and/or unpredictable claim construction positions and that multiple grounds are necessary to cover those possibilities. For example, in Shenzhen Liown Elecs. Co., Ltd. v. Disney Enterprises, Inc., the Petitioner argued that “[i]t is difficult to predict what [claim construction] positions [Patent Owner] will take here” and that multiple grounds were set forth “[t]o guard against [Patent Owner’s] ever-shifting claim interpretations.”16 The Petitioner then went on to show how each ground related to potential positions the Patent Owner might take.17 In its institution decision, the PTAB found that Petitioner “explains sufficiently why it included grounds based on these additional references.”18 One potential response from Patent Owners to this type of argument, however, might be to argue for a particular claim construction and that the grounds based on different claim constructions should be rejected as redundant.

Another strategy that has been used is to use references that have different disclosures with respect to the dependent claims. In Thorley Industries LLC v. Kolcraft Enterprises, Inc., the Petitioner argued that the eight grounds it presented were not redundant because only two grounds were directed to the same set of claims.19 The Petitioner also provided reasons why various references were “arguably superior to the others.”20 In rejecting Patent Owner’s arguments to the contrary, the PTAB instituted IPR proceedings on all eight grounds.21 The PTAB found persuasive that different references were relied on as teaching certain dependent claims.22The PTAB also found, with respect to the other grounds, that the Patent Owner had sufficiently offered “why each reference ‘is arguably superior to the others.’”23 Notably, the PTAB did not find fault with the fact that the Petitioner had not specifically pointed out the weaknesses, acknowledging that Petitioner “arguably has identified the relative strengths or weaknesses of these prior art references as they relate to certain limitations.”24

Another strategy that has been used is to argue that the relative strengths or weaknesses lie in the underlying statutory provisions that qualify each reference as prior art. For example, in Elekta, Inc. v. Varian Medical Systems, International AG, the PTAB found that the Petitioner had sufficiently presented reasons why the proposed grounds were not redundant because the primary ground was presented under 35 U.S.C. § 102(b), while the secondary ground was presented under 35 U.S.C. § 103(a).25 The PTAB found this argument persuasive, and noted that “Petitioner explains that it asserts [the] Tobler [Reference] in its grounds brought under 35 U.S.C. § 103(a) for the explicit purpose of addressing the possibility that the panel would be persuaded that the Earl Article is not enabling for purposes of anticipation.”26

Another option may be to argue that different reasons to combine references apply to the proposed combinations and are subject to attack differently by Patent Owner. For example, in Smith & Nephew, Inc. v. Arthrex, Inc., the PTAB found the asserted grounds were not redundant because the petition “relies on different references to establish different facts” for each ground and the second ground “relies on a different rationale for the proposed modification.”,27Accordingly, the PTAB may be receptive to arguments regarding the relative strengths or weaknesses of the grounds based on a comparison of the rationales to combine each reference.

IV. Conclusion

As the workload at the PTAB increases, Petitioners should look for creative ways to obtain favorable institution decisions. This may include presenting persuasive reasons why proposed grounds are not redundant. Even though institution of multiple grounds remains within the discretion of the PTAB regardless, Petitioners appear more likely to achieve a successful institution decision on multiple grounds if they present persuasive reasons why multiple grounds should be instituted, including reasons similar to those discussed in this article.


1 See USPTO, Patent Trial and Appeal Board Statistics, at 3 (March 31, 2017), available at (996 IPR petitions filed in FY17 as of March 31, 2017).
2 Harmonic Inc. v. Avid Tech., Inc., 815 F.3d 1356, 1368 (Fed.Cir. 2016) (stating that “it is clear that the Board may choose to institute some grounds and not institute others as part of its comprehensive institution decision.”); see also Shaw Indus. Grp., Inc. v. Automated Creel Sys., Inc., 817 F.3d 1293, 1298 (Fed.Cir. 2016) (“We can see benefit in the PTO having the ability to institute IPR on only some of the claims and on only some of the proposed grounds, particularly given the Board’s statutory obligation to complete proceedings in a timely and efficient manner.”).
3 See id. at 1299 (finding the Federal Circuit lacked jurisdiction to review the PTAB’s decision to deny certain grounds as “redundant”).
4 Id. at 1300 (finding the petitioner “did not raise—nor could it have reasonably raised—the [redundant] Payne-based ground during the IPR” (emphasis in original)).
5 See James Williams & Matt Prosen, Estoppel Under the AIA, Considerations for Strategic Use of ‘Redundant’ IPR Grounds, Baker Botts PTAB Blog, available at
6 Apple Inc. v. Parthenon Unified Mem. Arch. LLC, IPR2016-00923 (Aug. 23, 2016) (Paper 10), at 17, also available at 2016 WL 5404421 (internal quotation marks omitted).
7 See USPTO, Patent Trial and Appeal Board Statistics, at 3 (March 31, 2017), available at (996 IPR petitions filed in FY17 through March 31, 2017 compared to 1,565 in FY16);, Jobs, Join Us, available at (last accessed June 3, 2017) (“At this time, the USPTO has temporarily suspended hiring activity. By order of the president, there is a 90-day freeze on the hiring of civilian employees across all federal government agencies. As part of this freeze, ‘no vacant positions existing at noon on January 22, 2017, may be filled and no new positions may be created, except in limited circumstances.’ As a result, all hiring activities at the USPTO are deferred until further notice.”).
8 Conopco, Inc. v. Procter & Gamble Co., Case IPR2013-00505 (Paper 9), at 17 (PTAB Feb. 12, 2014), also available at 2014 WL 1253037.
9 Oracle Corp. v. Clouding IP, LLC, Case IPR2013-00088 (Paper 13), at 6 (PTAB Jun. 13, 2013) (request for reh’g denied), also available at 2013 WL 5970180.
10 Apple Inc. v. Virnetx, Inc., IPR2016-00331, (Paper 9), at 6 (June 30, 2016) (finding grounds not redundant despite there being no specific redundancy arguments in petition), also available at 2013 WL 5970180.
11 See James Williams & Matt Prosen, Estoppel Under the AIA, Considerations for Strategic Use of ‘Redundant’ IPR Grounds, Baker Botts PTAB Blog, available at
12 Apple Inc. v. Parthenon Unified Mem. Arch. LLC, IPR2016-00923 (Paper 2), at 5 (PTAB April 20, 2016).
13 Id. (Paper 10), at 16-17 (PTAB Aug. 23, 2016), also available at 2016 WL 5404421.
14 Micron Tech., Inc. v. Innovative Mem. Sys., IPR2016-00323 (Paper 11), at 16 (PTAB June 13, 2016), also available at 2016 WL 5028031.
15 Id. at 16-17.
16 Shenzhen Liown Elecs. Co., Ltd. v. Disney Enterprises, Inc., IPR2016-01834 (Paper 2), at 70 (PTAB Sept. 21, 2016).
17 Id. at 70-72.
18 Id. (Paper 11), at 23 (PTAB Mar. 9, 2017), also available at 2017 WL 950759.
19 Thorley Industries LLC v. Kolcraft Enterprises, Inc., IPR2016-00352 (Paper 1), at 59-60 (PTAB Dec. 16, 2015).
20 Id.
21 Id. (Paper 14), at 20-22 (PTAB June 23, 2016), also available at 2016 WL 5105565.
22 Id. (“In our view, [the] Johnston [reference] is not redundant of [the] Pasin [reference] for at least the reason that Petitioner relies on Johnston, but not Pasin, for teaching the limitations recited in claims 5 and 15.”).
23 Id. at 20.
24 Id. at 21 (emphasis added).
25 Elekta, Inc. v. Varian Medical Systems, International AG, IPR2016-00844 (Paper 9), at 29-30 (PTAB Sept. 28, 2016), also available at 2016 WL 6650768.
26 Id.see also Nxp Semiconductors Usa, Inc. v, Inside Secure, NFC Tech., LLC, IPR2016-00683 (Paper 10), at 26 n.8 (PTAB Sept. 8, 2016), also available at 2016 WL 5403571 (“We are satisfied that the grounds on which we institute inter partes review are sufficiently distinguished with each other, and with grounds asserted in other petitions, at least because they are based on different prior art (e.g., prior art under § 102(a) vs. prior art under § 102(b)).”).
27 Smith & Nephew, Inc. v. Arthrex, Inc., IPR2016-00817 (Paper 8), at 30-31 (PTAB Sept. 29, 2016), also available at 2016 WL 6650770.


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