The SEC officials investigating Elon Musk over his handling of the Twitter takeover seem to be growing more and more impatient with his legal antics. The two sides have been locked in a dispute over Musk’s refusal to testify in the investigation.Now, in a new filing, the SEC accuses Musk of trying to “misrepresent” the regulator’s investigation. “Musk continues to distort the true scope of this investigation – his only hope for establishing that the SEC is not seeking relevant evidence,” the SEC writes in a court document.

The SEC has been investigating Musk over his delayed disclosure of his stake in Twitter, which was then a publicly-traded company. The regulator Musk last year in an effort to force him to testify in the investigation. The SEC said it was investigating “among other things, potential violations of various provisions of the federal securities laws in connection with” his purchase of Twitter stock and “SEC filings relating to Twitter.” A federal judge ordered Musk to comply with the subpoena and schedule an interview .

That testimony has apparently still not taken place, with the SEC accusing Musk of using “gamesmanship” to stall the investigation. The regulator goes on to note that while Musk’s legal team has claimed the probe is an “unbounded investigation into an allegedly days-late SEC filing,” that “the SEC staff has repeatedly informed Musk that it is false.”

Musk, according to the SEC, is also being investigated for securities fraud. “This investigation also examines potential securities fraud in violation of Section 10(b) of the Securities Exchange Act … related to, among other things, Musk’s public statements about his acquisition of Twitter,” the SEC says.

Notably, the filing also references the recently-released y of Musk written by Walter Isaacson, which contains “newly released evidence,” according to the SEC. “Three days before he was to appear for the testimony he failed to attend, his September 2023 biography was published,” the SEC writes. “This book provides important new information relevant to the SEC’s investigation.”

It’s also not the first time Isaacson’s account of the Twitter takeover has landed Musk in hot water. A group of suing Musk over unpaid severance also referenced a passage from the book in their lawsuit.

X didn’t immediately respond to a request for comment.