Defendant
14 cases as defendant.
Overview. Metaswitch Networks (formerly Data Connection Ltd) is a UK-based telecommunications software company founded in 1981 by seven ex-IBM employees and headquartered in Enfield, England. It is a private operating company with a long history of private-equity and corporate ownership: Francisco Partners and Sequoia Capital took a controlling interest in 2008, Microsoft acquired the company in July 2020, and Alianza, Inc. completed its purchase of Metaswitch from Microsoft on March 4, 2025 (Microsoft retained the packet-core "Nexus" products). Reported headcount has ranged around 700–800; UK filings showed turnover of roughly £171M for the year ended August 2023. It is not publicly traded.
Products / services. Metaswitch develops carrier-grade, largely virtualized communications software for service providers and equipment manufacturers. Its Carrier Systems Division supplies session control, media gateway, application/feature server, and network management products supporting VoIP/IMS and unified communications, while its Network Protocols Division licenses portable protocol stacks (IP routing, MPLS, optical, ATM) to equipment vendors. It has acquired AppTrigger (2010), Colibria (2011), and OpenCloud (2017), and its Project Calico SDN work was spun out as Tigera.
Litigation posture. Metaswitch appears exclusively as a defendant (0 plaintiff cases, 3 defendant cases) — consistent with an operating company being targeted by competitor patent suits rather than a patent assertion entity. Two of the three tracked matters were filed in the plaintiff-friendly Eastern District of Texas, Marshall Division, and one is a Federal Circuit appeal.
Notable cases. Genband US LLC v. Metaswitch Networks Ltd. et al. (E.D. Tex., filed January 2014) and Sonus Networks, Inc. v. Metaswitch Networks Ltd. et al. (E.D. Tex., filed April 2018) were brought by rival softswitch/VoIP vendors; Genband and Sonus subsequently merged into Ribbon Communications, making the disputes part of a concentrated competitive rivalry in voice-network infrastructure. A related Genband US LLC v. Metaswitch Networks Corp. appeal was tracked at the Federal Circuit. The merits of these disputes are not assessed here.
Sonus Networks, Inc. sued Metaswitch Networks Ltd. and Metaswitch Networks Corp. in a case involving U.S. 6,885,658. The case was stayed pending appeal of the related -33 case, then settled and dismissed with prejudice in 2019.
Sonus Networks (later associated with Ribbon Communications) sued Metaswitch, with U.S. Patent No. 6,934,279 among the asserted patents. The parties mediated and settled; the case was dismissed with prejudice on July 1, 2019.
Sonus Networks sued Metaswitch Networks Ltd. and Metaswitch Networks Corp. in E.D. Tex., alleging continuing infringement of patents from the earlier 2:14-cv-00033 action and false advertising. The Stanford NPE Litigation Database lists this case as involving U.S. Patent No. 7,995,589. The parties settled and the court dismissed the case with prejudice on July 1, 2019.
Sonus Networks, successor-in-interest to Genband, sued Metaswitch in the Eastern District of Texas asserting U.S. 7,990,984. The parties settled through mediation, and the case was dismissed with prejudice on July 1, 2019.
Sonus/Ribbon alleged Metaswitch continued to infringe patents from the first lawsuit, including U.S. 7,184,427, through redesigned products, and also asserted willful infringement and false advertising. The case settled in 2019.
Genband US LLC sued Metaswitch Networks Ltd. and Metaswitch Networks Corp. for infringement of seven patents including U.S. 6,885,658. A jury found Metaswitch infringed all asserted claims, including '658 claims 1 and 11, and the claims were valid, awarding $8,168,400; final judgment was entered March 22, 2018.
Genband asserted the '589 Patent, including claim 15, along with six other patents against Metaswitch. A jury found infringement and validity on January 15, 2016, awarding $8,168,400; the court denied a permanent injunction and entered final judgment on March 22, 2018. The case was closed April 10, 2018.
Genband asserted U.S. 7,184,427, one of eight patents in the original complaint and seven at trial, against Metaswitch. A jury found infringement and no invalidity, awarding $8,168,400; after a bench trial and injunction denial, the court entered final judgment of about $8.9 million. Metaswitch appealed.
Patent infringement action brought by Genband US LLC against Metaswitch Networks Corp. in the Eastern District of Texas. The case is listed in the Google Patents litigation record for US 6,772,210 and closed on 2018-04-10; the narrative notes that specific assertion/adjudication of 6,772,210 was not independently confirmed.
Federal Circuit appeal of the district court's denial of a permanent injunction in the Genband v. Metaswitch dispute, involving U.S. 6,885,658. The Federal Circuit vacated and remanded, holding the district court may have applied an unduly strict causal nexus/drive demand standard for irreparable harm.
Federal Circuit appeal from the denial of a permanent injunction in the 2:14-cv-00033 action. The court vacated and remanded for reconsideration of the irreparable harm standard, expressly listing U.S. Patent No. 7,995,589 among the patents found infringed.
Appeal from the district court's September 2016 denial of Genband's permanent injunction. The Federal Circuit vacated and remanded, holding the district court may have applied too stringent a causal nexus standard for irreparable harm.
First Federal Circuit appeal from the Genband/Metaswitch district court case. The Federal Circuit vacated the district court's denial of a permanent injunction and remanded for reconsideration of the irreparable-harm standard.
Sonus Networks sued Metaswitch entities in the Eastern District of Texas, asserting the '971 Patent among other patents. The case was settled and dismissed with prejudice on July 1, 2019. The narrative notes conflicting filing dates (March 8, 2018 per SEC disclosure; April 18, 2018 per docket summary).