Elon Musk has taken a 9.2% stake in Twitter to become the platform’s biggest shareholder, according to a US securities filing.
After the announcement, Twitter's shares surged by more than 27% in New York trading on Monday. The stake is worth $2.89bn, based on Twitter's closing price on Friday.
Tesla's CEO owned 73,486,938 shares in the social media platform as of 14 March, according to the Securities and Exchange Commission.
Musk is a regular Twitter user with more than 80 million followers, although recently he said he is giving "serious thought" to building a new social media platform.