Musk, who bought Twitter in October 2022 and renamed it X, had started amassing shares earlier that year. His ownership amounted to more than 5% by March, requiring him to file a disclosure report. The SEC says the report was 11 days late, allowing Musk to "underpay by at least $150 million” for shares purchased before he disclosed his stake.

The Securities and Exchange Commission sued tech billionaire Elon Musk on Tuesday, accusing him of securities fraud linked to his $44 billion takeover of Twitter, now known as X.