AfterQuery Emerges as Y Combinator’s Quickest Unicorn, Valued at $3.2 Billion

AfterQuery, an emerging firm focused on AI training data, has reportedly obtained funding that boosts its valuation to $3.2 billion, merely five months after revealing a $30 million Series A funding round that valued the company at $300 million in April.

This remarkable progression represents an extraordinary increase of over 10 times in under six months, and as highlighted by Y Combinator partner Gustaf Alströmer, it marks the fastest ascent to unicorn status for any startup in the accelerator’s history. The founders of AfterQuery, aged 22 and 23, were part of Y Combinator’s Winter 2025 cohort just 18 months ago.

In April, the San Francisco-based company reported an annual revenue run rate of $100 million and emphasized its collaborations with top laboratories. Its impressive clientele includes prominent companies such as Nvidia, Legora, and Korea’s AI lab Motif Technologies.

AfterQuery stands at the forefront of a new wave of startups inspired by Mercor and Scale, partnering with professionals like doctors and lawyers for model training. Instead of simply providing accurate answers, AfterQuery aims to enable models and agents to operate like seasoned experts, effectively completing tasks—what the company describes as “encoding the patterns, decisions, and reasoning of the world’s most proficient practitioners.”

Forbes was the initial outlet to report on this funding round, and AfterQuery has yet to respond to inquiries for immediate comments.