The agency on Thursday asked a federal court to force Musk to testify for its investigation into his $44 billion takeover of social media giant Twitter, the third time the SEC has taken Musk to court.

It sued him in 2018 and again in 2019 in relation to a tweet Musk sent saying that he had funding secured to take his electric carmaker Tesla (TSLA.O) private. The 2018 lawsuit was quickly settled on the condition that lawyers vet Musk’s future tweets. The 2019 lawsuit by the SEC trying to enforce that deal did not go their way.

In this case, the SEC is on solid ground as the law enforcing the requirements of investigative demands, or subpoenas, is clear cut, said several former SEC officials.

While the stakes are lower this time, the new case again shines a spotlight on the extraordinary feud between the world’s richest man and most powerful securities regulator, which has for years struggled to bring Musk to heel.