The entrepreneur sold $3.3bn worth of Tesla stock on Tuesday and another $654m on Wednesday, according to filings with the Securities and Exchange Commission.
And on Friday morning, SEC filings showed that Mr Musk has sold another $4.5bn worth of shares as he raises the money needed to buy the social media platform.
Mr Musk is the world’s richest man with a personal fortune of $252bn, but most of his wealth is tied up in his Tesla stock.
Twitter’s board on Monday accepted Mr Musk’s offer of $54.20 per share in cash for total control of the company, that he has said he will take private.
The deal, which was unanimously recommended by the board, still needs to be ratified by shareholders and pass regulatory scrutiny.
Mr Musk, who has not confirmed exactly why he sold the shares, already owns nine per cent of Twitter.
On Thursday evening he took to Twitter and said, “No further TSLA sales planned after today.”
He has put up $21bn of his own money to buy the social media company and is borrowing another $12.5bn, while Morgan Stanley is funding another $13bn.
The 50-year-old is Tesla’s largest shareholder wit ha 17 per cent stake, and last year he sold more than $16bn worth.
The move came after Mr Musk asked his 88 million Twitter followers in a poll if he should sell ten per cent of his Tesla stock.
Mr Musk will likely make some significant changes to the social media platform, having made several hints in recent months about what his intentions are. It comes after Musk’s friend Jack Dorsey stepped down as CEO and Parag Agrawal took over.
Changes could include a new CEO, worker layoffs and even monetising tweets by charging publishers to embed them, according to some reports.