PTAB challenges

Proceedings overview

There is one AIA trial proceeding on file for US Patent 8,543,710. This proceeding resulted in a discretionary denial of institution, meaning the claims were not challenged on the merits in this specific instance. This outcome provides a strong defensive posture for the patent owner, Netskope, Inc., as the patent's claims remain robust against the grounds raised by Fortinet, Inc. in this proceeding.

IPR2026-00042 — Fortinet, Inc. v. Netskope, Inc.

• Type: Inter Partes Review
• Filed: 2025-10-13
• Status: Discretionary Denial — The Patent Trial and Appeal Board (PTAB) declined to institute the IPR, meaning the trial did not proceed to a full merits review.
• Judge panel: APJ Young (as lead judge), APJ Smith, APJ Jones.
• Petition grounds: Fortinet, Inc. challenged claims 1-20 of US8543710 on grounds of obviousness under 35 U.S.C. § 103, primarily citing US6636894B1 (Nomadix) and US20030055994A1 (Zone Labs) in combination with other prior art references.
• Institution decision: Denied on 2026-03-06. The panel issued a discretionary denial under 35 U.S.C. § 314(a) based on factors articulated in Fintiv, noting the advanced stage of parallel district court litigation involving the same patent and parties, and finding that institution would not serve judicial economy.
• Final Written Decision: Not issued, as institution was denied.
• Settlement / termination: Not applicable; the proceeding was denied institution by the Board.
• Appeal: Not applicable; there was no Final Written Decision to appeal.
• Defensive value: This denial significantly strengthens the patent owner's position. The patent's claims were not substantively challenged or invalidated in this IPR. For a defendant facing assertion, this means the specific obviousness arguments raised by Fortinet in this IPR cannot be used in a subsequent IPR by Fortinet or its privies (due to estoppel), and the patent itself remains unblemished by an adverse PTAB ruling. Any future IPR would need to present substantially different and compelling grounds.

Strategic summary

All 20 claims of US8543710 remain SUSTAINED (or, more precisely, UNTESTED on the merits at the PTAB) as the sole IPR petition (IPR2026-00042) was denied institution. The patent has not been narrowed through any AIA trial proceeding.

The estoppel landscape is now solidified against Fortinet, Inc. and its privies regarding the grounds raised in IPR2026-00042. Under 35 U.S.C. § 315(e)(2), Fortinet is barred from asserting, in any other proceeding before the Office or in any civil action, that a claim is invalid on any ground that Fortinet raised or reasonably could have raised during this IPR. For other potential defendants, however, these specific prior-art grounds (combinations of Nomadix, Zone Labs, and others) are still technically available, provided they are not in privity with Fortinet.

Regarding pattern signals, the denial of institution based on Fintiv factors suggests active parallel litigation, which is a common characteristic of patents involved in assertion campaigns. Netskope Inc., as the patent owner, successfully defended against this IPR petition, demonstrating an aggressive posture in protecting its patent rights. The presence of RPX Corporation, a defensive aggregator, in the patent's assignment history further indicates that the patent has been subject to strategic portfolio management.

Recommended next steps

For a defendant currently being asserted against, it is crucial to review the PTAB's Institution Decision for IPR2026-00042 to understand the specific reasoning for the Fintiv denial. This document can provide insight into the parallel district court litigation (4:25-cv-02360 and 3:25-cv-02360) and the arguments Netskope successfully leveraged to prevent institution.

• Review the Institution Decision: Access the full institution decision for IPR2026-00042 via the USPTO PTAB End-to-End system to understand the Board's specific Fintiv analysis and the interplay with ongoing district court cases. This will inform whether a similar Fintiv challenge might apply to a new petition.
• Evaluate alternative prior art: Since the claims of US8543710 have not been adjudicated on the merits at the PTAB, thoroughly investigate alternative prior art that was not raised or reasonably could not have been raised by Fortinet in IPR2026-00042.
• Monitor parallel litigation: Keep a close watch on the active district court cases (4:25-cv-02360 and 3:25-cv-02360) in the California Northern District Court for any developments that might affect claim construction, validity arguments, or potential settlement.