Data showed traders continuing to reduce bets against Tesla after short interest on Friday dipped to 26.9 percent of the company's float, the lowest since June, according to S3 Partners, a financial analytics firm.

"I'm seeing a little bit of covering, but it's not indicative of a change in conviction. It's more just people cutting a little fat off their trades," said Ihor Dusaniwsky, head of research at S3 Partners in New York.

Short interest in Tesla was equivalent to 27.2 percent of its float a week ago, before Musk shocked investors by saying on Twitter he was considering taking Tesla private at $420 a share and that funding was "secured," sending its stock sharply higher.

At $12.2 billion in short bets, Tesla remains the most shorted company in the United States, while globally, it is second only to Alibaba, at $24.3 billion, according to S3 Partners.

In a blog post, Musk said on Monday he was in talks with potential backers of a possible Tesla buyout, including Saudi Arabia's sovereign wealth fund, but had not completed securing the funding.

Investors have voiced doubts about Musk's ability to pull off what could be the largest-ever go-private transaction, valued at as much as $72 billion.

Tesla attracts extreme opinions on Wall Street. Mutual fund companies including Fidelity are confident of Musk's vision, while most analysts are sceptical about the stock's valuation and Tesla's ability to compete with larger rivals. On Twitter, Musk has repeatedly taunted short sellers.

“I think Tesla is in deep trouble, and he’s throwing a Hail Mary to see if he can get out of it,” said Vilas Capital Management Chief Executive John Thompson, who has a short position in Tesla.

Short-sellers borrow shares they believe are overpriced, sell them, and then repurchase shares later at what they hope will be a lower price to make a profit.

Musk's tweet on Tuesday about taking Tesla private is under scrutiny by the U.S. Securities and Exchange Commission, according to the Wall Street Journal, and is the subject of investor lawsuits.

Tesla's stock rose 0.26 percent on Monday to $356.41. It is up 4 percent over the past week and is about 15 percent below Musk's go-private price of $420.

(Reporting by Noel Randewich in San Francisco, additional reporting by Kate Duguid in New York; Editing by Cynthia Osterman and Susan Thomas)

By Noel Randewich