Session Link Research Sues Verizon in Marshall on Seven Network and Calling Patents.

Session Link Research LLC filed Session Link Research LLC v. Verizon Communications, Inc., No. 2:26-cv-00995 (E.D. Tex., Marshall Division), on November 3, 2026, against Verizon Communications, Inc. and Cellco Partnership d/b/a Verizon Wireless. The complaint describes the plaintiff as a Texas limited liability company based in Marshall, Texas, Verizon Communications as a Delaware corporation based in New York, New York, and Cellco as a Delaware general partnership based in Basking Ridge, New Jersey. The docket shows the case assigned to Judge Rodney Gilstrap and referred to Magistrate Judge Roy S. Payne. The plaintiff demands a jury.

The seven patents

The complaint asserts seven patents, each attached as an exhibit, which Session Link says it owns outright (paragraphs 10 to 17): U.S. Patent 9,961,209, "Codec Selection Optimization," issued May 1, 2018; U.S. Patent 9,392,436, "Method and Apparatus for Voice Over LTE," issued July 12, 2016; U.S. Patent 8,265,062, "System and Method for Accomplishing Special Call Treatment in a Voice Over Internet Protocol Telephone System," issued September 11, 2012; U.S. Patent 9,083,771, "System and Methods for Multi-Participant Teleconferencing Using Preferred Forms of Telecommunication," issued July 14, 2015; U.S. Patent 10,057,429, "Pre-Paid Voice Calling Using Sponsored Data Roaming," issued August 21, 2018; U.S. Patent 11,284,459, "Data Access Security," issued March 22, 2022; and U.S. Patent 10,979,462, "Identifying Voice Over LTE Users," issued April 13, 2021. The complaint says the named inventors developed the technology at one company, which each patent lists as its assignee.

The exemplary claims are claim 1 of the '209, '436, '062, and '462 patents, claim 11 of the '771 patent, claim 15 of the '429 patent, and claim 24 of the '459 patent (paragraphs 35, 50, 65, 82, 102, 119, and 135).

The complaint describes the '209 patent as providing listings of codecs for offers and answers, the '436 patent as a transit network that handles signaling messages between service provider networks, the '062 patent as special treatment of an internet telephone call routed from an originating gateway to a destination gateway, and the '771 patent as a teleconferencing system in which a telecommunication manager sets up connections with participants (paragraphs 24 to 27). It describes the '429 patent as a packetized data path for a roaming mobile device through visited and home networks to a calling service, with network and access information used to set a calling rate; the '459 patent as authenticating network and subscriber information in a session request and preventing the data tunnel when the request cannot be authenticated; and the '462 patent as querying an IP exchange with a subscriber's identifier to learn the subscriber's provisioned service and select how the communication is routed (paragraphs 28 to 30).

The accused network

The accused products are Verizon's 5G Ultra Wideband network, including the standalone 5G core, data centers, 5G and 5G Ultra Wideband base stations, 5G hardware, software, radio units, and baseband units, and associated equipment, services, and platforms such as Verizon Connect and ThingSpace (paragraph 22). The complaint alleges, on information and belief, that Verizon's 5G network, standalone 5G core, and IMS networks are designed and operated in compliance with 3GPP, GSMA, and IETF standards, including those governing VoLTE, VoNR, SIP and SDP signaling, codec negotiation, inter-operator connectivity, and roaming (paragraph 23).

Count by count, the complaint maps the '209 patent to codec negotiation in Verizon's 5G core and IMS core for VoNR calls, relying on 3GPP TS 23.228 and TS 24.229 for how interconnection border functions process SDP offers and answers; the '436, '771, and '429 patents to Verizon's 4G LTE and 5G networks that support IMS-based VoLTE and VoNR; the '062 patent to its 5G network with IMS-based voice services; and the '459 and '462 patents to Verizon's cloud-native 5G core, citing the GSMA FS.20 specification for GTP security at the interconnect edge and GSMA IMS standards for exchanging user and service information between networks.

What the complaint alleges

Each of the seven counts alleges direct infringement, induced infringement, and contributory infringement under 35 U.S.C. § 271(c). The complaint pleads knowledge at least as of the date of the complaint and, in the alternative, alleges on information and belief that the defendants were willfully blind through a policy of not reviewing the patents of others. For the '459 and '462 patents, it also alleges, in the alternative, knowledge no later than September 13, 2022, when two patents issued to a Verizon affiliate that, the complaint says, cite those patent families. It says Session Link has complied with the marking statute and, on information and belief, that prior assignees and licensees did too.

Relief requested

The prayer asks for a judgment that the defendants directly infringed one or more claims of each patent, a permanent injunction under 35 U.S.C. § 283, damages no less than a reasonable royalty with interest and costs, and an exceptional case finding with attorney fees under § 285 (pages 164 and 165).

Where the case stands

Through November 4, 2026, the docket shows the complaint with the seven patents as exhibits, the patent and trademark form, the plaintiff's disclosure statement, notices of appearance, and a summons issued to both defendants on November 4. Session Link Research filed three other patent suits in the Marshall Division the same day, Nos. 2:26-cv-00992, 2:26-cv-00994, and 2:26-cv-00996; the '436 patent is the one patent asserted in No. 2:26-cv-00996. Watch for service on both defendants and their answers or motions. The case can end at any time, including by settlement or voluntary dismissal.