T-Mobile US joined the growing list of companies to put Broadcom on their naughty list after the chip giant’s controversial VMware buyout.

Court documents seen by The Register revealed the telecom giant is moving off of VMware and legally demanding Broadcom’s support it believes the firm is bound to provide from a pre-acquisition VMware deal it signed in August 2023. That agreement gave it perpetual licenses for certain software, along with two years of support and an option to extend support for an additional year.

The documents reveal T-Mobile US’ business relationship with VMware began in 2008, with one court filing from Broadcom claiming that T-Mobile US runs VMware software across more than 303,000 central processing unit (CPU) cores. With this amount of virtual machine (VM) penetration, the carrier's counsel described the deployment as "the base of [T-Mobile US'] entire internal network."

Broadcom furthermore notified T-Mobile US in 2024 that it would not renew support once the initial two-year agreement expired last year, arguing that the contract was voided once it phased out the products concerned in favor of the cloud-subscription based VMware Cloud Foundation (VCF).

The companies continued discussing potential new arrangements, albeit after an alleged lack of proposals from Broadcom between August 2024 to May 2025., while T-Mobile US also sought an injunction requiring Broadcom to continue providing support. Broadcom opposed the request, arguing that T-Mobile US had waited too long to claim its injunction, which expires on August 3.

In a court transcript seen by this title, T-Mobile's counsel also highlighted the looming end-of-life as a telecom infrastructure risk, claiming it would risk “irreparable harm" to its network and customer data, while jeopardizing emergency responder voicemails.

Transition-Mobile

According to the report, T-Mobile US proposed paying $20 million for an additional two years of support, an arrangement that T-Mobile US VP of Technology Kevin Luu said would help “complete T-Mobile’s transition away from VMware at a more deliberate pace,” according to a filed affirmation.

The court ultimately granted the injunction, requiring Broadcom to continue providing support beyond August 2025. As part of the order, T-Mobile US was required to pay $5.28 million and post a $500,000 undertaking. Broadcom complied with the injunction but also sought damages, arguing that the court order prevented it from securing a new commercial agreement with T-Mobile US. The operator rejected that claim, noting that the two companies had continued negotiating a potential new deal throughout the period.

Broadcom later proposed charging $24 million for extended support covering six products, saying the price reflected the cost of maintaining a team of more than 20 staff to support T-Mobile US' environment. T-Mobile US disputed this by claiming it's only made two support requests so far in 2026.

AT&T precedent

Presiding over the case is The Honorable Jennifer Shecter, who also oversaw AT&T’s VMware divorce from Broadcom. That case saw the pair settle on a confidential settlement after AT&T branded the vendor a “bully” for forcing it into paying “a king’s ransom for subscriptions [it did] not want or need.”

According to The Reg, Judge Shecter said in a hearing from late last year that T-Mobile US' case “is even more compelling and to be sure I was very compelled both in AT&T and very convinced,” despite Broadcom arguing T-Mobile US was slower to the draw than AT&T in that particular contract dispute.

It also argued both operators were “outliers,” claiming a large number of its 10,000 largest customers – 90% according to CEO Hock Tan – have accepted the new state-of-play and already migrated successfully to the subscription model.

Judge Schecter was unconvinced by the claim, suggesting instead that some customers simply choose not to challenge the company or that smaller organizations find it easier to transition away from VMware.

Away from the U.S., Broadcom has also seen European blowback amid spats with Siemens and U.K. supermarket giant Tesco. The latter is reportedly racing to migrate 40,000 of its servers away in one of the largest VMware migrations to date amid its own court battle with the vendor. This lawsuit saw Tesco seek around $130 million in damages over its “very abusive conduct.”

Broadcom apparently negotiated various efforts with the retailer, with one proposal allegedly offering a year of VCF 9.0 along with mainframe software and associated support for $23.5 million – a 175% increase over its 2021 software agreement and a 350% jump for its mainframe services, according to Tesco.

It remains unclear at time of writing how T-Mobile US, which appears to have not started a similar migration race against time, will cope with its VMware backbone should it lose software support.