Musk and the SEC have regularly clashed over the last decade, with the Twitter deal the latest flashpoint between the two.

Last month, Musk failed to appear to testify after four months’ notice, according to the SEC. The sides had an agreed-upon date, but two days beforehand, Musk canceled, “raising, for the first time, several spurious objections,” the SEC said.

Alex Spiro, an attorney representing Musk, said in an email: “The SEC has already taken Mr. Musk’s testimony multiple times in this misguided investigation – enough is enough.”

The SEC stated in the order that Musk objected to questions about why the agency needed him to testify again, the location of the testimony and the fact that a biography about the billionaire came out in September that his lawyers needed time to review.

“None of Musk’s objections has any legal validity, and he has no justifiable excuse for his non-compliance with the SEC’s subpoena,” the agency wrote in the order.

The tensions between the SEC and Musk date back to the Tesla CEO’s tweets in 2018 discussing a deal to take the electric car manufacturer private at $420 per share. Soon after, the SEC filed and settled fraud charges against Musk — leading to his ouster as Tesla chair and a $20 million penalty. Musk later in the year went on the “60 Minutes” television show to declare he does “not respect the SEC.”

Musk recently lost a courtroom fight over the terms of the settlement, though Spiro has said he plans to appeal to the Supreme Court.