Elon Musk has offloaded 4.4 million shares of Tesla stock worth approximately $4 billion, most likely to fund his acquisition of Twitter (NYSE: TWTR). Musk disclosed the sale in a Securities and Exchange Commission filing. The shares have been sold in recent days at varying prices from $872.02 to $999.13.

Musk recently disclosed that he has decided to buy Twitter for $44 billion on Monday. The CEO of Tesla, the world's richest man, tweeted that he has no plans to sell any more of the company's stock. The majority of the sales occurred on Tuesday, when Tesla shares fell 12 percent in a single day, a massive drop.

On Monday, the billionaire and Twitter entered into an agreement for the world's richest man to purchase the social-media company. According to analysts, Tesla investors are concerned that Musk will become preoccupied with Twitter and less involved in running the electric car company. Musk has served as CEO of Tesla since 2008 and has long held the majority stake. Meanwhile, confirmation of his sales could be unsettling for shareholders, many of whom are retail investors.

Furthermore, the Twitter acquisition is expected to be one of the largest leveraged buyouts in history, with Musk obtaining $25.5 billion in debt and margin loan financing from lenders including Morgan Stanley. If the agreement is dissolved, the party who dissolved it will be obligated to pay a $1 billion termination fee under certain conditions.

Twitter shares closed Thursday at $49.11, falling short of the $54.20 per share that investors will receive under the company's agreement with Musk. Musk sold millions of Tesla shares valued at more than $16 billion near the end of 2021. It was his first sale in more than five years. They began in November when he asked his Twitter followers if he should sell his stake in the automaker, which happened to coincide with a decrease in the stock.