Setting precedent on whether a party may use joinder under § 315(c) to add new issues to its own petitions, the Precedential Opinion Panel (POP) of the Patent Trial and Appeal Board (PTAB) determined that in very limited circumstances, a party may join new issues to its own previously filed inter partes review (IPR) petition. Proppant Express Investments, LLC v. Oren Techs., LLC, Case No. IPR2018-00914 (Mar. 13, 2019) (Boalick, ACAPJ). Granting a request for rehearing, the POP resolved conflicting decisions on (1) whether a petitioner may be joined to a proceeding in which it is already a party, (2) whether § 315(c) permits joinder of new issues into an existing proceeding, and (3) whether the § 315(b) time bar may affect the first two questions.

Proppant Express Investments (PropX) filed a first IPR petition. After institution, PropX filed a second petition to add a new reference to correct “mistakes” in the prior petition. Because the second petition otherwise would have been time-barred, PropX filed a motion under § 315(c) for joinder with its first petition. The panel recognized a split among various PTAB decisions and held that § 315(c) was limited to joining new parties, and that a party was prohibited under § 315(c) from adding new issues to its earlier petitions (IP Update, Vol. 21, No. 12). PropX sought rehearing, and the POP granted rehearing to address the conflicting decisions.

The POP determined that § 315(c) allows for a petitioner to join a proceeding in which it is already a party and provides discretion for the PTAB to allow joinder of new issues into an existing proceeding. Reviewing the statute’s phrase “any person” in the context of the statute and congressional record, the POP declined to limit the interpretation to only those persons who are not already a party to a proceeding. The POP rejected the argument that consolidation of multiple petitions under § 315(d) was the only appropriate vehicle by which a party could seek joinder of its own petitions. The POP noted that joinder under § 315(c) and consolidation under § 315(d) provided two separate and distinct ways of managing parallel US Patent and Trademark Office proceedings, each having different requirements and limitations.

The POP also concluded that the time bar under § 315(b) is one of several factors that may be considered when the PTAB exercises its discretion under § 315(c). However, the POP noted that the PTAB should exercise its discretion only in limited circumstances—namely, where fairness requires it and to avoid undue prejudice to a party. Mistakes or omissions by a petitioner generally do not qualify. Other circumstances, such as actions taken by a patent owner in a co-pending litigation to add newly asserted claims, may be such a circumstance.