Elon Musk is joining Twitter’s Board of Directors a day after disclosing that the Tesla CEO took 9.2% stake in the social media platform. Twitter Inc. said in a regulatory filing on Tuesday that it entered into an agreement with Musk on Monday that will give the billionaire a seat on its Board, with the term expiring at its 2024 annual shareholders meeting. Musk, either alone or as a member of a group, won’t be allowed to own more than 14.9% of Twitter’s outstanding stock for as long as he’s a Board member and for 90 days after.

Twitter CEO Parag Agrawal said in a tweet the company had been talking to Musk in recent weeks and “it became clear to us that he would bring great value to our Board.” “He’s both a passionate believer and intense critic of the service which is exactly what we need on @Twitter, and in the boardroom, to make us stronger in the long-term,” Agrawal continued. Musk, who has 80 million Twitter followers, has also raised the possibility with his massive and loyal Twitter following, that he could create a rival social media network.