Reddit mascot Snoo is seen on the floor of the New York Stock Exchange (NYSE) as Reddit begins trading in New York on March 21, 2024.

Timothy A. Clary | AFP | Getty Images

OpenAI CEO Sam Altman says he has no equity in the $80 billion AI startup he co-founded in 2015.

His Reddit ownership is another matter entirely.

After Reddit’s stock market debut on Thursday, Altman’s stake in the social media site grew by $200 million to more than $613 million. Shares of the 19-year-old company jumped 48% in New York Stock Exchange trading to close at $50.44.

Altman, 38, is among Reddit’s largest shareholders, controlling 7.6% of the shares outstanding after the offering, according to company data prospectus. That’s behind only Condé Nast Advance Magazine Publishers and the Chinese Internet giant Tencent.

Like other insiders, Altman is restricted from selling Reddit stock for six months during a so-called lock-up period.

Before OpenAI emerged in recent years, largely due to the popularity of its chatbot ChatGPT, Altman was best known as a startup investor and as president of Y Combinator, a position he left in 2019. Altman’s investment portfolio includes past or present shares in Airbnb, Uber, Instacartstripe and Asana.

Reddit was one of his best bets. He even sat on the company’s board until around January 2022, when the company said he recently retired.

In 2014, Altman led Reddit’s $50 million Series B funding round after using the service every day for nine years, he wrote in blog post. He called the website “an example of something that started out as a silly time-wasting toy and turned into something very interesting.”

In 2021, when the tech market was booming, Altman invested a total of $60 million in Reddit over two funding rounds. Those investments have yet to bear much fruit, as Reddit’s valuation, even after Thursday’s rally, is below the peak of the private market. Reddit filings show Altman invested $50 million at $42.47 per share and $10 million at $61.79 per share.

However, the money he accumulated a decade ago has multiplied many times over.

This has helped ease the pressure on Altman when it comes to profiting from OpenAI, where his tenure has been controversial for other reasons. Late last year, Altman was briefly fired by OpenAI’s board, which said it had lost confidence in his leadership. It was brought back days later after massive pressure from employees and investors.

Earlier this month, OpenAI said Altman would rejoin its board following the conclusion of an internal investigation by US law firm WilmerHale into the events that led to his ouster.

Altman told the senators in a hearing last May that he didn’t take his current gig because of the money. Notes show that he earned about $73,500 in total compensation in 2022.

“I get paid enough for health insurance, I don’t have equity in OpenAI,” Altman said when asked by Sen. John F. Kennedy, R-La., if he makes a lot of money in his job. “I do this because I love it.”

— CNBC’s Jonathan Vanian and Jordan Novett contributed to this report

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