Elon Musk’s X is updating its Terms of Service to indicate it still lays claim to the “Twitter” trademark. The move to add this detail to the company’s terms follows an announcement from a Virginia-based startup, which recently filed an application to trademark the term “Twitter.”

The startup, Operation Bluebird, claims that X had abandoned the brand “Twitter” by renaming its social networking service “X.” In its petition to the U.S. Patent and Trademark Office filed on December 2, the startup pointed to a post from X owner Musk on July 23, 2023, which proclaimed that the social network would soon “bid adieu to the twitter brand.”

X is now challenging that claim with a countersuit of its own. (A copy of the filing was shared with TechCrunch via IP trademark law firm Gerben IP; it’s not yet showing in PACER as of the time of publication.) In the filing, X says that it continues to exclusively own the Twitter and Tweet trademarks and the bluebird logo.

Since filing its petition for cancellation, Operation Bluebird has been collecting potential user sign-ups for its own social network at a website named Twitter.new. The effort is headed up by two lawyers, including founder Michael Peroff, based in Illinois, and Stephen Coates, previously a trademark lawyer at Twitter. Given their backgrounds, their assertion that they plan to launch a new service to rival X seems dubious. It’s more likely they want to acquire the trademark, which has value of its own.

Nevertheless, X isn’t taking its chances. Its revised Terms of Service, effective as of January 15, 2026, states:

Nothing in the Terms gives you a right to use the X name or Twitter name or any of the X or Twitter trademarks, logos, domain names, other distinctive brand features, and other proprietary rights, and you may not do so without our express written consent.

Previously, the terms only referenced X in this section. There was no mention of Twitter.

The terms additionally include other, more minor updates, including mentions related to EU laws and generated content. X’s Privacy Policy was also updated with a couple of references to age assurance technology.

This article was updated with a link to the countersuit following its initial publication.