The US Securities and Exchange Commission (SEC) filed a lawsuit against Elon Musk on Tuesday, alleging he failed to disclose his ownership of X (formerly Twitter) in a timely manner, violating federal law, as reported by CNN and journalist Ramishah Maruf.

According to the SEC, Musk began acquiring Twitter shares in early 2022 and exceeded 5% ownership by mid-March. However, he delayed disclosure until 4 April, allowing him to purchase shares at “artificially low prices,” allegedly underpaying investors by over $150 million.

Musk’s lawyer, Alex Spiro, told CNN the lawsuit is a “baseless complaint” and accused the SEC of harassment.

The complaint, filed in DC federal court, claims Musk’s non-disclosure impacted Twitter’s stock price ahead of his $44 billion acquisition in October 2022.