Elon MuskHas been accused Microsoft co-founder Bill GatesShorting Tesla.

The Tesla CEO, in tweets on Friday, admitted to Gates that he inquired about short-selling Tesla shares. Short-selling a stock means that investors are betting on the fall in the value of the asset.

Musk stated in a tweet that he had heard several people at TED tell me Gates was still short half a billion against Tesla.

He was responding to a Twitter user’s questionOn whether the screengrab of what appeared to be a text conversation between two billionaires is real.

Tesla Chief replied, “Yeah but I didn’t leak it to NYT. It must have been through friends of their friends.

In the text exchange, which couldn’t be independently verified by CNBC, Musk asked Gates:

Gates then replied, “Sorry that I haven’t shut it out. It would be a pleasure to speak with you about the possibilities of philanthropy.

Musk responded: “Sorry. Your philanthropy regarding climate change is not serious when you take a huge short position against Tesla. Tesla has the greatest potential to resolve climate change.”

CNBC was unable to reach Bill Gates for comment at this time.

Gates said NYT opinion writer Kara Swisherlast year: “It was important to note that Elon made with Tesla one of climate change’s greatest contributions.” It’s a bad idea to underestimate Elon.

However, he said that Tesla was only doing “easy stuff”, such as passenger cars. Gates stressed the importance of addressing other industries to have a bigger impact on climate change.

He stated that “we’re not doing enough for the hard stuff,” which included steel, cement, and meat. “And sadly, the things people think about — the electricity, passenger cars — are a third of the problem. We must work with the other three-thirds.

You miss what the hardest part of the lead-time if you focus only on the short-term metrics.

The public spat between these two men isn’t the first.

When Gates revealed in 2020 that he bought himself an all-electric Porsche Taycan, a Twitter user asked: “I wonder why Bill Gates decided to go with the Taycan instead of a Tesla.”

Musk responded in a tweet: [to be honest].”

Musk previously speculated about the possibility that Gates might shorten his stock. If he had been short Tesla in the past, he would have to answer questions about these comments. Gates told CNBC last year– “I don’t speak about my investments, but I believe he should feel very proud of the things he’s done.”

In a Bloomberg interview also in February 2021Gates stated that he would have liked to be more “on the long side of Tesla” when he was asked about Musk’s claims.

— CNBC’s Todd Haselton and Ryan Browne contributed to this report