April 26, 2022: -Elon Musk has accused Microsoft co-founder Bill Gates of shorting Tesla.

On Friday, the Tesla CEO admitted that he asked Gates if he was short-selling shares of the electric carmaker. When investors short a stock, they are betting that the asset’s price will decrease.

“I heard from many people at TED that Gates still had half-billion short against Tesla, which is why I asked him, so it’s not exactly top secret,” Musk said in the tweet.

He responded to a Twitter user’s question on whether a screengrab of a supposed text conversation amid the two billionaires was real.

The Cheif of Tesla responded, “Yeah, but I didn’t leak it to NYT. They must have got it through mutuals.”

The account that inquired regarding the text messages, @wholemarsblog, heavily promotes Tesla and Elon Musk and is among the few handles that Musk most interacts with on Twitter.

Omar Qazi running @wholemarsblog is a co-defendant with Elon Musk in a libel and harassment lawsuit brought by Aaron Greenspan, founder of the public records database Plain site. The latter has also shorted Tesla stock and been a vocal critic of Elon Musk.

In the text exchange, which CNBC couldn’t independently verify, Musk asked Gates: “Do you still have a half-billion-dollar short position against Tesla?”

Gates replied, “Sorry to say I haven’t closed it out. I want to discuss philanthropy possibilities.”

Musk commented, “Sorry, I cannot take your philanthropy on climate change seriously when you have a massive short position against Tesla, the company doing the most to solve climate change.”

In the previous year, gates told New York Times opinion writer Kara Swisher: “It’s important to say that what Elon did with Tesla is one of the greatest contributions to climate change anyone’s ever made. And you know, underestimating Elon is not a good idea.”

But he went on to add that what Tesla was doing was “easy stuff, like passenger cars.” Gates emphasized the need to make a more significant impact on climate change by tackling other industries.

“We’re not doing enough on the hard stuff: steel, cement, meat,” he said. “And sadly, the things people think about the electricity, passenger cars are a third of the problem. So, we have to work on the two-thirds.”

“If all you pay attention to is those short-term metrics, not the green premiums across the board, you miss out on the longest lead time, which is the hard stuff.”