Sam Altman's Reddit stake value surpassed $1 billion following a post-earnings increase.

• After hours trading, Sam Altman's stake in Reddit is now valued at more than $1 billion.
• The OpenAI CEO is among Reddit's largest shareholders.
• Altman served on the company's board until approximately January 2022, when Reddit announced that he had recently resigned.

As of post-market trading on Tuesday, Sam Altman, CEO of OpenAI, has a stake in a social media company worth over $1 billion.

Reddit shares surged about 20% in extended trading after the company reported better-than-expected quarterly results and issued an optimistic forecast.

Altman's holdings are valued at approximately $1.2 billion at the after-hours share price of $98 on Reddit.

Prior to the release of OpenAI's ChatGPT in late 2022, Altman was best known as a startup investor and as the former president of Y Combinator. Altman's investment portfolio includes past or present stakes in Airbnb, Uber, Instacart, Stripe, and Asana, but one of his top bets was Reddit. Altman was on Reddit's board until around January 2022, when the company announced that he had recently stepped down.

Reddit went public in March at $34 a share.

Altman is one of the largest shareholders of the company, following only Advance Magazine Publishers, Tencent, and Fidelity. In 2021, Altman invested $60 million in Reddit across two funding rounds, as stated in the company's IPO prospectus from this year.

During the "lockup period," which ended in September, top shareholders were prohibited from selling Reddit shares for six months. There is no evidence that Altman has sold any of his stock.

Altman didn't immediately respond to a request for comment.

This month, OpenAI concluded its latest funding round at a valuation of $157 billion, with $6.6 billion raised from a diverse group of investors and tech companies. Despite expecting a loss of approximately $5 billion on $3.7 billion in revenue this year, CNBC confirmed in September.

Last month, Altman informed employees that there were no plans for him to receive a substantial equity stake in the company.

Late last year, OpenAI announced that Altman was rejoining its board after an internal investigation by U.S. law firm WilmerHale into the events that led to his sudden ouster.

— CNBC's Ari Levy contributed to this report

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