Y Combinator owns an approximate 0.6% stake in OpenAI. This previously non-public holding is worth over $5 billion according to a report from Daring Fireball.
The stake originated in 2016 when YC Research seeded the startup.
OpenAI established an $852 billion post-money valuation during a March 2026 funding round. The company raised $122 billion during that specific financing event.
This disclosure surfaces amid broader discussions regarding the incentives and affiliations of key AI industry figures.