It appears Instagram and FB owner Meta holds the trademark for "X" as it relates to "online social networking services... social networking services in the fields of entertainment, gaming and application development..." https://tsdr.uspto.gov/#caseNumber=87980831&caseType=SERIAL_NO&searchType=statusSearch via @[email protected]
Trademark Status & Document Retrieval

@taylorlorenz marvellous. They can fight for it in their cage match.
@taylorlorenz @alexweprin Wait… are you telling me that the current administration at Twitter didn’t properly look into something before plowing ahead with it?

@taylorlorenz @[email protected] ah. So this whole things was an attempt to sell Twitter to Meta?

Complicate...

🙄

@taylorlorenz @[email protected] while it's amusing, I think it won't be an issue. I believe that Meta have rights for that particular graphical lettermark design, but not literally the letter X itself: