SAS Institute Inc. v. Iancu

SAS Institute Inc. petitioned for inter partes review (IPR) of a software patent owned by ComplementSoft, challenging all 16 claims. The Patent Trial and Appeal Board (PTAB) instituted review on only some of the claims and issued a final written decision solely on those, leaving the remaining claims untouched. SAS appealed, arguing that 35 U.S.C. § 318(a) requires the PTAB to issue a final written decision on every claim challenged in the petition. The Federal Circuit upheld the PTAB's partial institution practice. The Supreme Court granted certiorari and, in a 5-4 decision written by Justice Gorsuch, held that the plain text of the statute mandates that once the PTAB institutes an IPR, it must decide the patentability of all claims the petitioner has challenged, not just a subset. This ruling eliminated the PTAB's ability to pick and choose claims.

The Supreme Court reversed the Federal Circuit, holding that 35 U.S.C. § 318(a) unambiguously requires the PTAB to address all claims challenged in the IPR petition. The PTAB's practice of partial institution was contrary to the statutory text.

Whether the Patent Trial and Appeal Board must issue a final written decision on every claim challenged by a petitioner in an inter partes review, or whether it may limit its decision to only some of the challenged claims.

The decision ended the PTAB's long-standing partial institution practice, forcing the board to issue a complete determination on every challenged claim. It increased procedural certainty, reduced the potential for serial IPR petitions, and reshaped USPTO rules and litigation strategies. Patent owners and petitioners alike adjusted to the all-or-nothing review framework, reinforcing the IPR system as a comprehensive alternative to district court litigation.