An article from The Daring Fireball mentioned the percentage of OpenAI owned by YC. According to a source known to the author, that share is approximately 0.6%.
Y Combinator Estimated to Hold Approximately 0.6% Stake in OpenAI, Valued at Over $5 Billion
This article is a translation. Read the Japanese original
OpenAI's current valuation stands at $852 billion. Based on this figure, YC's stake is estimated to be worth more than $5 billion.
During the OpenAI board turmoil in 2023, Paul Graham commented on Sam Altman's credibility. However, it has been pointed out that Graham himself is a co-founder of YC and holds an indirect financial interest in OpenAI.
Graham stated, "I didn't fire Altman." At the same time, he has not provided a clear guarantee that Altman is honest. This raises questions about how to interpret his opinions given the stakes involving hundreds of millions of dollars.
Source: Y Combinator's Stake in OpenAI (0.6%?)（HN 378pt・68コメント） (HN Search (backfill), 2026-05-05)