The Writingstar Investment Guildaccount suspended from Twitter last year for tracking the movements of Elon Musk's private jet has landed on a rival social media app: Threads.

"Elon Musk's Jet" made its first post to the new site last week, with owner Jack Sweeney writing: "ElonJet has arrived to Threads!"

An offshoot of Instagram, Threads debuted on Wednesday and allows users to post text. Meta CEO Mark Zuckerberg said in a post on Friday that the app already had 70 million new sign-ups.

Also on Wednesday, an attorney for Musk-owned Twitter said the website may take legal action against Threads, accusing the app of "systematic, willful, and unlawful misappropriation of Twitter's trade secrets and other intellectual property."

Meta officials have dismissed the allegations, with communications director Andy Stone saying that "[n]o one on the Threads engineering team is a former Twitter employee."

Sweeney, a Florida college student, gained notoriety for the Twitter account that posted public transponder information from Musk's private plane, showing where it took off and landed.

After Musk bought Twitter for $44 billion last year, the billionaire CEO said he would allow the account to remain on the site in the spirit of free speech but later backtracked and suspended it.

Musk tweeted at the time that Twitter would suspend any "account doxxing real-time location info" for posing a "physical safety violation." Accounts that posted location information on a delay could remain, he added. Musk also threatened to sue Sweeney.

Sweeney later returned to Twitter with the account, ElonJet but Delayed, which posts information on Musk's plane on a 24-hour delay. He also has similar accounts on other social media platforms, including Instagram and Bluesky.

Musk's private jet isn't the only one Sweeney tracks. He also posts information about planes used by Zuckerberg, former President Trump, Florida Gov. Ron DeSantis, Jeff Bezos, Kim Kardashian and Taylor Swift.