The U.S. Securities and Exchange Commission is looking into Elon Musk’s acquisition of Twitter shares shortly before he bought and rebranded the social media company. In response, the billionaire is allegedly exploring the legal strategy of simply not showing up to give testimony.

The SEC is now looking to force Musk to show up to an interview after he bailed on one last month. Just the latest scheduled meeting between the regulator and the billionaire, the rendezvous had already been rescheduled once.

Musk had agreed to an interview with the SEC on September 15, but on September 13, raised some objections, reports Bloomberg. The businessman claimed that San Francisco was not an appropriate venue for the interview, so investigators agreed to reschedule the meeting, and move it to Fort Worth, Texas, closer to where he lives now.

Read: DOJ May Seek Criminal Charges Against Elon Musk Over Tesla Perks

 Elon Musk Refused SEC Interview Over Twitter Stock Probe, Now Regulators Want Him To Talk

However, the billionaire then refused to meet at all, and did not show up to the interview with the SEC. Now, the regulators are seeking a subpoena, which is a rare move for the organization, but one it normally succeeds in getting judges to agree to.

Meanwhile, an attorney for Musk, Alex Spiro, said “enough is enough,” and that the billionaire has already given the SEC testimony multiple times in “this misguided investigation.”

The regulator is looking into stock purchases made by Musk in 2022. Before acquiring Twitter, the Tesla CEO bought 9.2 percent of the company in March. Although he disclosed the purchase to the SEC in April, that was not within the 10-day timeframe that the SEC requires of people who buy more than five percent of a public company.

The SEC began its investigation almost immediately, in April 2022, and has asked for thousands of documents from Musk and others. However, it said that the billionaire has only provided it with hundreds of documents, and spoken to it twice.

Just one of the investigations that the SEC has launched against Musk, the businessman is also being probed for making potentially inappropriate statements about Tesla’s self-driving technology, and fined him $20 million for tweets he made about Tesla’s stock.

 Elon Musk Refused SEC Interview Over Twitter Stock Probe, Now Regulators Want Him To Talk