Tesla boss Elon Musk has bought a 9.2% stake in Twitter.
Mr Musk purchased approximately 73.5 million shares, according to a regulatory filing on Monday.
He has been raising questions about the ability to communicate freely on Twitter, tweeting last month about free speech and the social media platform.
“Free speech is essential to a functioning democracy. Do you believe Twitter rigorously adheres to this principle?” he tweeted.
In a separate tweet, Mr Musk said he was “giving serious thought” to creating a new social media platform.
Also last month, Mr Musk asked a federal judge to nullify a subpoena from securities regulators and throw out a 2018 court agreement in which Musk had to have someone pre-approve his posts on Twitter.
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