Twitter says federal authorities are investigating Elon Musk in connection with his attempt to buy Twitter for $44 billion.

While Musk reversed course and said he would now go ahead with the planned purchase Twitterinformation about the alleged federal investigations only came to light in a recent court filing from the social media giant.

Twitter claims Elon Musk’s lawyers provided a “privilege log” of documents in September that will not be made available for discovery in a lawsuit over the failed deal. Those magazines cited drafts of a May 13 email to the US Securities and Exchange Commission (SEC) and slide presentations to the Federal Trade Commission (FTC).

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Delaware judge Kathleen McCormick asked to order Musk’s lawyers to produce the documents on October 6, but the trial was suspended that day after the world’s richest man changed his mind and said he would continue the deal with buy Twitter.

Reuters notes that the SEC has previously questioned Musk, including whether he disclosed his 9 percent stake in Twitter too late and why he initially said he would be a passive shareholder. In June, the SEC also asked Musk whether he should amend his public filings to reflect plans to suspend or abandon the planned Twitter takeover.

It is understood the FTC also looked into whether Musk failed to comply with antitrust reporting requirements that confirm an investor’s intent to be a passive or active shareholder.

Elon Musk has until October 28 completed the acquisition of Twitter. If that doesn’t happen, both sides will appear in court in November.