The US Court of Appeals for the Federal Circuit affirmed a Patent Trial & Appeal Board inter partes review (IPR) decision, finding that:
- § 314(d) does not bar review of an IPR petition’s scope.
- Substantial evidence supported the Board’s findings that the prior art taught the disputed limitations.
- The Board correctly distinguished similar but different claim elements.
International Business Machines Corp. v. Zillow Group, Inc., Case Nos. 24-1170; -1274 (Fed. Cir. Dec. 9, 2025) (Chen, Taranto, Stoll, JJ.)
IBM holds a patent related to systems and methods for single sign-on (SSO) operations, enabling users to create and access multiple accounts using a single set of login credentials. Rakuten petitioned for IPR, asserting an anticipation challenge under § 102 and three obviousness challenges under § 103. The Board instituted review and addressed three claim limitations central to the dispute.
The Board first addressed the “protected resources” limitation. It adopted IBM’s construction requiring URLs or URIs and ultimately found the anticipation challenge unmet, but not because Sunada prior art failed to disclose the limitation. Instead, Rakuten (the original IPR petitioner) expressly abandoned its § 102 anticipation ground at oral argument, and afterward the Board found that Rakuten had not carried its burden. However, the Board agreed that a prior art reference nonetheless satisfied the limitation because the Board concluded that a skilled artisan would understand Sunada’s express disclosure that “web applications” be identified by conventional URLs or URIs.
Next, the Board construed “identifier associated with the user” to mean information that uniquely identifies a user, adopting IBM’s preferred construction. The Board found that the prior art reference disclosed this limitation through its use of a “User ID.”
Finally, the Board determined that Rakuten failed to establish that the asserted prior art taught the limitation requiring the second system to send a request message to a first system “in response to a determination” during user account creation. The prior art disclosed sending such a request only to the user’s own computer (not to the first system) when additional user information was needed.
The Board held several challenged claims unpatentable and others not unpatentable based on the asserted prior art. IBM appealed regarding all the claims the Board found unpatentable, contending that the Board’s analysis of “protected resources” relied on a theory of patentability not raised in the reward company’s petition, and that the Board’s findings on “identifier associated with the user” lacked substantial evidence. Zillow cross-appealed with respect to all claims the Board held not unpatentable, arguing that the Board’s findings lacked substantial evidence.
The Federal Circuit affirmed the Board on both appeals. First, responding to Zillow’s reviewability challenge, the Court held that § 314(d) did not bar review of whether the Board stayed within the petition’s grounds. The Court explained that while institution decisions are unreviewable, courts routinely examine whether the final written decision relies on theories actually presented in the petition. Zillow argued that because IBM’s challenge was “closely tied” to the Board’s institution decision, § 314(d)’s bar on reviewability applied. As the Court explained, “while § 314(d) does bar us from reviewing a challenge ‘closely related to [the Board’s] decision whether to institute inter partes review,’ . . . it does not prevent us from examining whether the inter partes review ‘proceeds in accordance with the law’s demands.’” The Court concluded that IBM was “not seek[ing] to ‘undo’ institution” but was only trying to raise the issue of whether the Board’s final written decision stayed within the confines of the petition for IPR.
On the merits, the Federal Circuit rejected IBM’s argument that the Board relied on an unpled obviousness theory for the “protected resources” limitation. The Court concluded that the Board’s reasoning was consistent with the anticipation theory raised in the petition and did not modify the prior art or rely on new grounds.
The Federal Circuit also rejected IBM’s substantial-evidence challenge concerning the “identifier” limitation, agreeing that the prior art user ID that was transmitted as part of “information regarding the user” satisfied the Board’s construction requiring unique identification.
In addressing Zillow’s cross-appeal, the Federal Circuit rejected Zillow’s contention that the Board inconsistently treated two claims. Although the limitations in two challenged claims (one found unpatentable and one not unpatentable) were similar, the claim found not unpatentable required that the second system send a request to the first system, whereas the claim found unpatentable required that the request be sent to the user’s computer. Because the prior art taught requesting missing information from the user, but not from the first system, the Court found that substantial evidence supported the Board’s divergent outcomes for the two claims.
