Long Horizon Sues Fortinet in Marshall Over a Firmware Signature Patent.

The case

The case is Long Horizon Technologies LLC v. Fortinet Inc., No. 2:26-cv-00950 (E.D. Tex.), a 10-page complaint for patent infringement filed October 21, 2026, in the Marshall Division. Long Horizon is a Texas limited liability company with its principal place of business in Marshall, Texas. The complaint alleges, on information and belief, that Fortinet Inc. is a Delaware corporation with a regular and established place of business in the district, in Frisco, Texas. Subject-matter jurisdiction is pleaded under 28 U.S.C. 1331 and 1338(a), and venue under 28 U.S.C. 1400(b) and 1391(b) and (c). The complaint demands a jury trial. The docket shows an unopposed application for an extension of time to answer the complaint, filed October 27, 2026, and a clerk's entry on that application the same day.

The patent and what claim 1 covers

U.S. Patent 8,738,894, entitled Methods for Firmware Signature, issued May 27, 2014, from an application filed April 22, 2013. Long Horizon alleges that it is the sole and exclusive owner of all right, title, and interest in the patent and holds the exclusive right to enforce it, and that it has complied with the marking provisions of 35 U.S.C. 287.

USPTO assignment records list three recorded assignments of the patent: from the inventors to Rockwell Automation Technologies, Inc., recorded April 22, 2013 (reel 30259, frame 0447); from Rockwell Automation Technologies, Inc. to IP3 2025, Series 925 of Allied Security Trust I, executed November 12, 2025, and recorded November 24, 2025 (reel 73012, frame 0620); and from Longleaf Technologies LLC to Long Horizon Technologies LLC, executed October 12, 2026, and recorded October 21, 2026, the day the complaint was filed (reel 76457, frame 0290).

The complaint describes the patent as generally relating to methods for installing embedded firmware. Claim 1 covers a method that receives, by a first device, signature unaware firmware code, and installs that code on the first device via boot code configured for installation of both signature aware and signature unaware firmware code, where installing the signature unaware firmware code further comprises verifying, via at least one feedback mechanism, that the signature unaware firmware code is received from a second device associated with a user that has physical access to the first device.

The accused products

The complaint alleges that Fortinet has infringed and continues to infringe by making, using, offering to sell, selling, and/or importing products that update or facilitate the update of signature unaware modules with signature-aware firmware. Accused products include numerous FortiGate physical appliance series, FortiGate 6000/7000 and Rugged appliances, FortiFirewall appliances, FortiOS firmware including the 6.x, 7.x, and 8.x families, associated FortiGate BIOS/bootloader firmware-installation software, corresponding FortiFirewall firmware, and FortiManager firmware-management/deployment software, among other Fortinet products. The complaint uses the Fortigate-1001F as an exemplary mapping to claim 1, alleging receipt of signature-unaware FortiOS firmware, installation via BIOS or bootloader configured for newer and older FortiOS versions, and verification via feedback mechanisms that the firmware is received from a second device associated with a user with physical access to the appliance.

The counts

Count I asserts direct infringement of the '894 patent under 35 U.S.C. 271, literally or under the doctrine of equivalents, including at least claim 1. The complaint also alleges induced infringement of one or more claims by knowingly and intentionally inducing customers and end users, with knowledge of the patent at least as of the complaint date, and contributory infringement under 35 U.S.C. 271(c). It alleges, on information and belief, that Fortinet has adopted a policy of not reviewing the patents of others and so remained willfully blind to the patent. Long Horizon alleges damages and irreparable harm.

The relief sought

The prayer asks for a judgment that Fortinet has directly and/or indirectly infringed one or more claims of the patent; a permanent injunction under 35 U.S.C. 283; damages not less than a reasonable royalty, with interest and costs; a finding that the case is exceptional with costs and reasonable attorney fees under 35 U.S.C. 285; and further relief the court deems just and proper.

What to watch next

Watch for action on the extension application, Fortinet's answer or Rule 12 motion, Marshall Division scheduling, and any claim construction focused on claim 1's signature unaware firmware, boot code, feedback mechanism, and physical-access limitations.