The FTC is looking at whether Elon Musk's initial 9% stake in Twitter violated antitrust rules, report says

• The Federal Trade Commission has opened up an inquiry into Elon Musk's early stake in Twitter, The Information reported Thursday.
• The regulator aims to determine if Musk violated antitrust reporting requirements when he amassed a 9% stake earlier this year.

While Elon Musk has clinched a $44 billion takeover deal for Twitter, the Federal Trade Commission has opened up an inquiry into whether his initial stake in the social platform violated reporting requirements, sources told The Information Thursday.

Musk amassed a 9.2% stake between January and April of this year, and the investigation aims to clarify if the Tesla CEO bought the shares with the intention to influence Twitter's management, or if he intended to remain a passive shareholder, according to The Information.

Musk's stake initially had been disclosed via a 13G filing, which indicates a passive stake, or when a shareholder doesn't try to exert influence.

But a subsequent 13D filing, instead, confirmed that the Tesla chief was to be an active investor looking to hold sway over Twitter's business and operations. Twitter CEO Parag Argrawal also announced that the company would be appointing Musk as a board member, signaling his status as an active investor.

Separately, some have questioned whether Musk failed to disclose his 73.5 million Twitter shares on time. He had reported it three weeks after he passed the 5% threshold.

Shares of Twitter rose 1.6% to $49.40 on Thursday, still below Musk's acquisition price of $54.20 a share.

This wouldn't be his first run-in with financial watchdogs. In 2018, the Securities and Exchange Commission charged the billionaire with misleading investors after saying — via Twitter — he was considering taking Tesla private and had secured the necessary funding.

While the SEC eventually reached a settlement with Musk, it included an agreement that Tesla would have to approve any of Musk's tweets that included information that could move the company's stock price. And this part of the deal has come under recent contention.