Elon Musk, the CEO of Tesla, sold $4 billion worth of the company's stock following the Twitter board's decision to sell the social media company to the multi-billionaire.

According to filings with the Securities and Exchange Commission on Thursday, Musk sold 4.4 million shares of the electric car manufacturing company's stock for an average price of $903.58 on Tuesday and Wednesday. The sales account for only 2.6 % of the Tesla shares he fully owned at the start of Tuesday's trading session and less than 2% of his overall Tesla holdings when stock options he controls are factored in.

The reason for the transaction is not disclosed in the documents, according to a report from CNN.

"No further TSLA sales planned after today," Musk stated in a tweet Thursday evening, but it was unclear whether Musk had made any additional transactions since Wednesday that had not been disclosed.

No further TSLA sales planned after today

— Elon Musk (@elonmusk) April 29, 2022

Insiders like Musk are required to record purchases and sales of their company's stock to the SEC to keep the rest of the investment community informed. However, they have a few days to process the filing while still adhering to the regulations.

Worried Tesla Investors

Investors may have sold Tesla shares this week, worried that Musk would not be able to devote as much time and attention to the company. The corporation has aggressive expansion goals and is facing increasing competition.

Tesla's stock barely moved on Wednesday and Thursday. In premarket trade on Friday, the stock was up 3%.

Musk is anticipated to fund his purchase of Twitter with his large Tesla assets. That doesn't mean he has to sell all of his stock to cover the entire purchase price. Instead, he can borrow money by using the shares as collateral.

According to corporate documents, Musk has already committed 88.3 million Tesla shares as collateral as of June 30, 2021, but those shares were pledged years ago when Tesla shares have valued at a fraction of what they are now.

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He would probably be able to borrow more money using some of those shares as collateral. Even with the recent drop in Tesla's share price, the estimated 79 million unpledged shares he owns following Tuesday's sales might be used to loan $17 billion.

Tesla Stocks Drop This Week

Tesla stock lost ground on Thursday amid investor concerns that Musk may have to sell Tesla shares to fund his $21 billion equity contribution to his $44 billion Twitter buyout.

Tesla stock fell on Thursday as investors feared Musk would have to sell Tesla stock to cover his $21 billion equity contribution to Twitter's $44 billion acquisition, per Fox News.

After the social media company board accepted his buyout offer on Tuesday, the carmaker's stock market value plummeted by more than $125 billion.

Musk stated that he would contribute $21 billion of his personal assets to the $44 billion deal. Investors are concerned, though, that he may have to sell Tesla stock to help fund the buyout, according to BBC.

Musk is the wealthiest person on the planet, with a net worth of about $250 billion, largely due to his Tesla ownership.

He also owns more than 40% of the space company SpaceX, which is valued at over $100 billion.

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