The US Securities and Exchange Commission has sued billionaire Elon Musk, saying he failed to disclose his ownership of Twitter stock in a timely manner in early 2022, before buying the social media site.

As a result, the SEC alleges, Musk was able to underpay "by at least USD 150 million" for shares he bought after he should have disclosed his ownership of more than 5 per cent of Twitter's shares. Musk bought Twitter in October 2022 and later renamed it X.