United States: PTAB Confirms It Will Apply Broad Petitioner Estoppel Post-SAS

Last Updated: November 14 2018
Article by Lisa M. Mandrusiak


The IPR estoppel provision was originally intended as a check against patent challengers attacking patents serially in the USPTO or other forums based on grounds that were raised or "reasonably could have been raised" in the original IPR. Although the Federal Circuit has interpreted estoppel narrowly, district courts were split, and estoppel's impact has remained in flux for several years.

The Federal Circuit decisions led some petitioners to present multiple unpatentability grounds in their IPR petitions with the expectancy that some grounds would be denied institution and therefore preserved against estoppel. But, the U.S. Supreme Court's recent SAS Institute Inc. v. Iancu decision—leading to "all or none" institution decisions—has eliminated this approach as a viable strategy. Narrow interpretation is no longer supportable, as it would only estop the exact same grounds raised and instituted upon in an earlier petition, rendering the words "reasonably could have raised" meaningless. And this week, the PTAB confirmed that it will apply estoppel broadly post-SAS. Accordingly, once a final written decision issues, estoppel applies to all grounds instituted upon as well as those that reasonably could have been raised.

Scope of Estoppel

35 U.S.C. § 315(e)(1) and (2) are the statutory provisions regarding petitioner estoppel in IPRs. These provisions dictate that, after a final written decision is issued, a petitioner (and its real parties in interest and privies) are estopped from asserting in a subsequent USPTO proceeding, district court case, or ITC investigation "any ground that petitioner raised or reasonably could have raised" during the IPR in other proceedings before the USPTO, in district court, or in the ITC.

Although the language "any ground that petitioner raised or reasonably could have raised" during the IPR appears straightforward, the Federal Circuit indicated that estoppel should be applied narrowly. In Shaw Indus. Group, Inc. v. Automated Creel Systems, Inc., the Federal Circuit took a very literal interpretation of the statute, which refers to grounds that the petitioner "raised or reasonably could have raised during" the IPR, as opposed to those which were raised or could have been raised in a petition for IPR.

Although the Federal Circuit narrowly interpreted estoppel, it is unclear how narrow the Federal Circuit intended it to be, leading to a split in the district courts that have grappled with this issue.

A number of courts strictly applied Shaw's narrow interpretation of 35 U.S.C. § 315(e) by focusing on the language of the statute and the Federal Circuit's literal reading. For example, in Intellectual Ventures I LLC v. Toshiba Corp., Judge Sue L. Robinson (now retired) held that estoppel did not extend to references that were never presented to the PTAB, saying "although extending the [Shaw] logic to prior art references that were never presented to the PTAB at all (despite their public nature) confounds the very purpose of this parallel administrative proceeding, the court cannot divine a reasoned way around the Federal Circuit's interpretation in Shaw." 221 F. Supp. 3d 534, 553–54 (D. Del. 2016).

Similar reasoning—resulting in narrow estoppel—has been applied by judges in the Northern District of California, the Central District of California the District of New Jersey, and the District of Massachusetts.

Several other courts, including the District of Delaware (creating an intra-district split), the Northern District of Illinois, the Middle District of North Carolina, the Eastern District of Texas, the Eastern District of Virginia, and the Western District of Wisconsin have found that IPR estoppel extends beyond grounds that were included in an IPR petition by interpreting Shaw to carve out only an exception for grounds raised in a petition but not instituted upon.

Based on the number of courts applying broad estoppel, this is currently the majority view, even though it arguably contradicts the Federal Circuit.

But, the SAS Institute Inc. v. Iancu decision appears to eliminate this narrow-interpretation "loophole." Narrow interpretation is no longer viable, as it would only estop the exact same grounds raised and instituted upon in an earlier petition, rendering the words "reasonably could have raised" meaningless. Accordingly, the scope of estoppel has been clarified. Post-SAS, if institution is denied, there is no estoppel. And conversely, if trial is instituted and a final written decision is issued, estoppel applies to all grounds raised in the petition as well as those that reasonably could have been raised.

PTAB Applies Estoppel Broadly

This week, the PTAB confirmed that it would be adopting this interpretation (consistent with the district court majority view). This is unsurprising because, even before SAS, the PTAB limited Shaw and applied a broad standard for IPR estoppel. See, e.g., Great West Casualty Co. v. Intellectual Ventures II LLC, IPR2016-01534, Paper 13 (PTAB Feb. 15, 2017). In this case, the PTAB specifically rejected the argument that Shaw limits estoppel to grounds actually raised during the IPR as that argument would render superfluous the statutory words of "or reasonably could have raised." Thus, the panel in Great West Casualty limited the Shaw exception to grounds actually presented in a petition that was denied institution.

Now, post-SAS, this interpretation has been confirmed. In Kingston Tech. Co., Inc. v. Spex Techs., Inc., the PTAB denied institution of a second petition based on estoppel. IPR2018-01002, Paper 12 (PTAB Nov. 6, 2018). Although the Petitioner argued that estoppel should not apply based on Shaw, the PTAB distinguished Shaw as being a pre-SAS decision. (Slip op. at 5-6). The PTAB explained Petitioner's argument could not be correct post-SAS because "under Petitioner's interpretation of the statute, a petitioner is only estopped from raising again the exact same grounds that it raised in an earlier petition. Petitioner's interpretation would render the words "or reasonably could have raised" of subsection 315(e) meaningless." (Id. at 7.) Legislative history also supports the PTAB's broad interpretation. (Id. at 8.) Thus, "regardless of the reasons" Petitioner chose not to file a petition asserting these grounds at the time of filing its first petition, Petitioner was now estopped and the petition was dismissed. (Id. at 9.)

Best Practices

In view of this decision, best practices dictate that petitioners should err on the side of caution and assume that anything that could have been raised in the petition—i.e., arguments based on patents and printed publications—will be estopped in later proceedings. Thus, petitioners should put forth their best arguments in the IPR.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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