Elon Musk's deal for Twitter is back on - and now short-seller Hindenburg Research is dumping all its shares in the takeover target

• Elon Musk's deal to buy Twitter is back on, according to an SEC filing.
• Hindenburg Research said it would dump its entire long position in Twitter after Musk revived his proposal.

Famed short-seller Hindenburg Research sold all of its Twitter shares after Elon Musk revived his $44 billion deal to buy the social-media company.

Musk proposed restarting talks to buy Twitter Monday, prompting Hindenburg to offload its entire long position.

"We have closed our long position in Twitter," Hindenburg tweeted Tuesday.

Hindenburg, which became well-known criticizing and shorting companies including Nikola, Kandi Technologies, and Lordstown Motors, has been both long and short on Twitter this year.

In May, it opened and closed a short position after arguing that Musk would likely either look to renegotiate or walk away from his takeover deal.

It then bought Twitter shares in July in a bet that Musk's deal would collapse after the billionaire attempted to terminate his merger agreement.

"We have accumulated a significant long position in shares of Twitter," Hindenburg said when it disclosed its long position three months ago. "Twitter's complaint poses a credible threat to Musk's empire."

It has now dumped that stake with a deal back on the table after Musk proposed restarting talks to buy Twitter at $54.20 a share.

His backtracking means he could avoid a costly courtroom battle. Twitter sued Musk in July for trying to back out of the Twitter acquisition, saying that he was obligated to complete the deal.

Twitter jumped 39.8% from $37.22 to $52.02 in the time that Hindenburg owned the stock. It slipped 1.75% to $51.09 early Wednesday.

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