PTAB challenges

Proceedings overview

A single AIA trial proceeding has been filed against US patent 8327426. This proceeding, IPR2026-00026, resulted in a discretionary denial of institution, meaning no claims were adjudicated on their merits by the PTAB. From a defensive posture, the patent has survived one IPR challenge at the institution stage, making it hardened against the specific petitioner for the grounds that could have been reasonably raised. All claims of the patent remain untested by a full PTAB trial.

IPR2026-00026 — Fortinet, Inc. v. Netskope, Inc.

• Type: Inter Partes Review
• Filed: 2025-10-07
• Status: Discretionary Denial. This means the Patent Trial and Appeal Board (PTAB) exercised its discretion not to institute the inter partes review, often for reasons unrelated to the merits of the prior art, such as existing parallel district court litigation or policy considerations.
• Judge panel: The specific panel of Administrative Patent Judges for this proceeding is not publicly available from the search results. In early 2026, institution decisions were made by the Director in consultation with at least three PTAB judges as part of a centralized process.
• Petition grounds: The specific claims challenged, prior art asserted, and statutory bases (§ 102 / § 103 / § 112) of the petition are not publicly available from the search results.
• Institution decision: Denied institution. While the exact date of the institution decision for IPR2026-00026 is not explicitly stated in the provided search results, the proceeding's "last modified" date of 2026-03-02 indicates a decision was rendered around that time. The denial was a discretionary denial, likely based on factors such as those outlined in Fintiv precedent concerning parallel district court litigation, or potentially the newer factors introduced by Director Squires in March 2026 that consider U.S. manufacturing footprint and small business status.
• Final Written Decision (if issued): Not issued, as institution of the IPR was denied.
• Settlement / termination: Not applicable, as the IPR was not instituted.
• Appeal: Not applicable, as institution was denied. Decisions denying institution are generally considered non-appealable to the Federal Circuit.
• Defensive value: The patent owner, Netskope, Inc., successfully prevented institution of this IPR. This means the patent claims challenged in this petition remain unchallenged through a PTAB final written decision. Fortinet, Inc., and its privies, are now estopped under 35 U.S.C. § 315(e)(2) from asserting in other venues the grounds raised or that reasonably could have been raised in this petition. For other potential infringers, this proceeding has no direct impact on their ability to challenge the patent.

Strategic summary

US patent 8327426 has been the subject of only one PTAB proceeding, IPR2026-00026, which concluded with a discretionary denial of institution. Consequently, all claims of US8327426 are now UNTESTED on their merits by the PTAB; none have been canceled or sustained through a final written decision. The patent's scope remains undiminished by PTAB proceedings.

Regarding the estoppel landscape, Fortinet, Inc., as the petitioner in IPR2026-00026, along with its privies, is statutorily estopped under 35 U.S.C. § 315(e)(2) from asserting invalidity grounds under §§ 102 or 103 that were raised or reasonably could have been raised in that petition in any subsequent civil action or International Trade Commission (ITC) proceeding. However, this estoppel does not apply to other potential defendants who were not parties or privies to this IPR. These other parties retain the full range of prior-art grounds available for challenging the patent's validity.

The patent owner, Netskope, Inc., acquired the patent from RPX Corporation in July 2024, indicating a potential strategy to assert the patent. The discretionary denial of IPR2026-00026, especially in the context of ongoing parallel district court litigation (Netskope, Inc. v. Fortinet, Inc., Case No. 4:25-cv-02360-HSG in the Northern District of California), aligns with a broader trend at the PTAB in early 2026. Under Director John Squires's leadership, there has been a centralization of institution authority and a shift towards policies that increasingly favor patent owners through discretionary denials, often considering factors like the stage of parallel litigation (Fintiv factors) and domestic manufacturing presence.

Recommended next steps

For a defendant facing assertion of US8327426 today, the primary consideration is that the patent's claims have not been subjected to a full validity review by the PTAB.

• Given the PTAB's current environment emphasizing discretionary denials, any potential new IPR petition should be carefully strategized. Petitioners must thoroughly address and distinguish their case from the PTAB's prevailing discretionary factors, particularly the Fintiv factors (e.g., the stage of any parallel district court litigation, overlap of invalidity contentions between forums) and the Director's new guidance on U.S. manufacturing and small business status, if applicable.
• Currently, no PTAB proceedings are active for US patent 8327426. The absence of instituted IPRs, despite a challenge, could be interpreted as a signal of the patent's resilience under the current PTAB discretionary institution policies.