Sectra Sues Verizon in East Texas Over a Network Handover Patent.

The parties and the patent

The case is Sectra Communications AB v. Cellco Partnership d/b/a Verizon Wireless, No. 2:26-cv-00930 (E.D. Tex.), assigned to Judge Robert W. Schroeder III. The defendants are Cellco Partnership d/b/a Verizon Wireless, MCI Communications Services LLC d/b/a Verizon Business Services, and Verizon Communications Inc. The complaint says Sectra is a Swedish corporation based in Linköping, Sweden; that Cellco, which it calls a Delaware corporation, is based in Basking Ridge, New Jersey; that MCI Communications Services is a Delaware company based in Ashburn, Virginia; and that Verizon Communications Inc. is a Delaware corporation based in New York, New York, and the ultimate parent of the other two.

U.S. Patent 7,797,437, titled Method for Handover Between Heterogeneous Communications Networks, issued September 14, 2010, to inventors Torbjorn Hovmark and Lars Resenius. The face of the patent names Columbitech AB of Stockholm, Sweden, as assignee. It issued from Application No. 10/432,547, the U.S. national stage of PCT/SE01/02612, filed November 26, 2001, and the face shows a 1,965-day patent term adjustment. The complaint says Sectra learned of the patented technology around 2010, when its Tiger secure telephone line faced session persistence and handover problems, and later licensed it from Columbitech and acquired Columbitech and all of its assets, including the patent, in early 2019.

Claim 1 is a method of maintaining communication between a geographically mobile first unit and a second unit, each of which has a protocol stack between its communications hardware and its software components. The method gives each unit a session layer that acts as an interface between its protocol stack and its software components, has each session layer indicate an identity for the other unit, and has the two session layers use a common session protocol so that traffic from different sockets on one side is directed to uniquely corresponding sockets on the other. The first unit is provided with communications hardware and drive routines for different networks. When the first unit switches from the first network to a third network, its session layer maintains the communication by selecting the hardware and drive routines that network needs, while the second unit's session layer retains its identity for the first unit through the switch.

Claims 2 through 21 all depend from claim 1. Among other things, claim 18 has the switching unit tell a third unit its new IP address so the second unit can get the address from it, and claims 19 and 20 make that third unit an SIP registrar server or a Mobile-IP Home Agent. Claims 22 and 23, the patent's computer-readable-medium claims, are not among the claims the complaint names. The complaint says the asserted claims are method claims and that, for that reason, its damages are not limited by 35 U.S.C. 287.

Google Patents' litigation listing for the '437 patent also links two other Eastern District of Texas suits filed March 3, 2026, Sectra Communications AB v. Cisco Systems, Inc., No. 2:26-cv-00174, and Sectra Communications AB v. Fortinet, Inc., No. 2:26-cv-00175, both assigned to Judge Schroeder, and an earlier suit against Absolute Software, No. 2:22-cv-00353 (W.D. Wash.), which the docket shows closed on November 12, 2024. Google Patents still lists Columbitech AB as the current assignee of the '437 patent.

What the complaint alleges

The complaint defines the accused instrumentalities as Verizon mobile devices; Verizon's wireless network infrastructure, including the IMS Core, the Evolved Packet Data Gateway (ePDG), carrier configurations, SIP signaling parameters, and session management software; and any product or service that supports Wi-Fi Calling or similar handover between Wi-Fi and cellular networks. It also accuses Verizon's zero trust and mobile VPN offerings, naming Verizon Zero Trust Dynamic Access (which it says, on information and belief, is powered by iboss), Verizon Secure Gateway Services, Verizon Mobile Private Network, and Verizon Private IP. A claim chart is attached as Exhibit 2.

There is one count. It alleges direct infringement under 35 U.S.C. 271(a) of at least claims 1 through 21, by Verizon itself or through an agent, through use of the accused instrumentalities, and induced infringement under section 271(b) by customers, partners, and end users, citing Verizon support pages and product descriptions as the instructions. No contributory infringement theory is pleaded. The complaint alleges, on information and belief, that the three defendants act in concert and as agents of one another, and it pleads that their acts are attributable to each other under agency or alter ego principles.

On knowledge, the complaint alleges, on information and belief, that Verizon has known of the patent since at least January 4, 2013, when Columbitech's president sent Verizon personnel a written overview that identified the patent after a December 18, 2012 meeting, followed by a more detailed version on January 14, 2013. It also alleges earlier contacts: a June 2006 business value proposition Columbitech addressed to Verizon Wireless, which it alleges on information and belief Verizon received, and, on information and belief, a July 2010 Verizon product evaluation report on Columbitech's session persistence and network roaming technology. The complaint pleads, on information and belief, that Verizon knew of the patent and its scope, alleges willful infringement and, in the alternative, willful blindness, and seeks enhanced damages.

Venue is pleaded under 28 U.S.C. 1391 and 1400(b). The complaint points to Verizon retail stores in Plano, Frisco, Allen, Marshall, Longview, Texarkana, and Tyler, network facilities in Frisco, and earlier Eastern District of Texas cases in which, it says, Verizon admitted or did not contest venue.

Relief requested

The prayer asks for a judgment of direct and indirect infringement; damages under 35 U.S.C. 284, including supplemental damages for any post-verdict infringement and an accounting; ongoing royalties after final judgment; a judgment that infringement has been willful, with treble damages; pre-judgment and post-judgment interest; costs; and attorney fees under 35 U.S.C. 285. The prayer does not ask for an injunction. Sectra demands a jury. Its counsel are Edward R. Nelson III, Brent N. Bumgardner, Christopher G. Granaghan, Carder W. Brooks, and Jinming Zhang of Nelson Bumgardner Conroy PC in Fort Worth, Texas.

Patent term

The complaint does not state an expiration date. Google Patents lists the '437 patent as active, with an adjusted expiration date of April 14, 2027.

What to watch next

Watch for the Verizon defendants' answer or a Rule 12 motion, including any challenge to the pre-suit knowledge and willfulness allegations or to patent eligibility, which the complaint addresses in advance in paragraphs 20 through 29.

Watch for whether any defendant contests the agency and alter ego theory the complaint uses to tie the three Verizon entities to this District.

Watch for any order relating or consolidating this case with the Cisco and Fortinet cases before Judge Schroeder.

Watch for any petition for inter partes review of the '437 patent. The case can also end at any time, including by settlement or voluntary dismissal.

Verizon is also a defendant in an unrelated Eastern District of Texas suit on fiber network patents: TechSys Insights Sues Verizon Over Fiber and Network Patents.