Greenlight Capital’s David Einhorn thinks speculative behavior in the current bull market has ascended to a level beyond common sense.

“We have reached the ‘Fartcoin’ stage of the market cycle,” Einhorn wrote in an investor letter obtained by CNBC. “Other than trading and speculation, it serves no other obvious purpose and fulfills no need that is not served elsewhere.”

A crypto token called “fartcoin” exploded in popularity as the re-election of Donald Trump unleashed a storm of animal spirits on Main Street. The meme coin is now edging towards a $2 billion market value, surpassing many U.S.-listed companies.

More meme coins have emerged since the inception of fartcoin. President Donald Trump launched $TRUMP, a meme coin built on the Solana platform. Its market cap over the weekend climbed past $14 billion. The coin at one point was down more than 20% over the past 24 hours, but it has since cut its losses to around 3%. Trump’s wife Melania also unveiled a coin.

“Nothing stops the launch of many more tradable coins,” Einhorn said. “Perhaps we are leaving the Fartcoin stage of the market and entering the Trump (and Melania) memecoin stage. It’s anyone’s guess as to what will happen next, but it feels like it’s going to be wild.”

Einhorn’s letter comes as investors drive equities higher, buoyed by expectations of lower taxes and deregulation from the second Trump administration. On Tuesday, the day after the inauguration, the Dow Jones Industrial Average rallied more than 400 points. The S&P 500 and Nasdaq Composite climbed 0.8% and 0.7%, respectively.

Shorting leveraged bitcoin ETFs

Greenlight took advantage of the craziness around crypto during the fourth quarter by betting against some popular ETFs linked indirectly to bitcoin.

The two funds the firm focused on were the T-Rex 2X Long MSTR Daily Target ETF (MSTU) and the Defiance Daily Target 2X Long MSTR ETF (MSTX). Those funds use derivatives to try to achieve two-times the daily returns of MicroStrategy, a software company that has turned itself into a bitcoin treasury vehicle in recent years.

The funds have at times struggled to achieve that goal due to MicroStrategy’s volatility and little supply of the derivatives most easily used to get the leveraged returns.

The letter said Greenlight took short positions against those funds during the quarter, partially offset by owning MicroStrategy stock in an arbitrage trade that was a “material winner.”

Bitcoin will hit a new all-time high in 2025 on the back of positive regulatory movements in the U.S. under newly inaugurated President Donald Trump, the CEO of Binance told CNBC Tuesday.

Richard Teng, who took the reins from former Binance boss Changpeng Zhao last year, told CNBC’s Arjun Kharpal that he sees “much clearer regulation” happening in the U.S. this year under the new Trump administration, adding this will be supportive for crypto markets.

“If you look at past cycles, this year will be a year that we see a new all-time high for the crypto industry,” Teng said in a fireside chat at the World Economic Forum in Davos, Switzerland.

Bitcoin passed the $100,000 price milestone for the first time last year, as traders grew optimistic about the crypto industry’s prospects under a Trump administration. As of Tuesday, the token was trading near $104,000, according to CoinGecko, down 3% in the last 24 hours amid a broad slump in crypto markets.

“The narrative [around crypto] has shifted quite drastically” since last year, Teng added, noting he’s been hearing positive crypto sentiments expressed by political and corporate leaders since arriving in Davos.

In terms of new legislation, Teng said that he expects to see progress in the United States on several fronts, including token issuance, trading and asset management.

Trump isn’t the only key U.S. political figure who is “pro-crypto,” Teng said, adding: “The House of Representatives and the Senate now [are] pro-crypto, compared to the past.”

“So, legislation will be passed, you have pro-crypto regulators being appointed to key commissioner roles in the SEC and CFTC,” Binance’s CEO said.

Trump picked respected Washington lawyer Paul Atkins to lead the Securities and Exchange Commission, which has previously been aggressive in its enforcement approach to the crypto industry

Teng is also expecting Trump to give the crypto sector “certainty” and “recognition,” as well as establish a U.S. strategic bitcoin reserve — something the now-president suggested he’d do during his campaign.