AfterQuery Achieves Unicorn Status as Y Combinator’s Fastest, with a Valuation of $3.2 Billion

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

This marks an extraordinary growth of more than 10 times in under six months and, as highlighted by Y Combinator partner Gustaf Alströmer, represents the fastest ascent to unicorn status for any startup in the accelerator’s history. The founders of AfterQuery, who are 22 and 23 years old, were part of Y Combinator’s Winter 2025 cohort merely 18 months ago.

In April, the San Francisco-based firm disclosed an annual revenue run rate of $100 million and emphasized its collaborations with prominent laboratories. Noteworthy clients feature major companies such as Nvidia, Legora, and Korea’s AI lab Motif Technologies.

AfterQuery is part of a new wave of startups inspired by Mercor and Scale, which partner with professionals like doctors and lawyers for model training. Instead of just providing accurate answers, AfterQuery aims to enable models and agents to operate like seasoned experts, effectively completing tasks—what the company refers to as “encoding the patterns, decisions, and reasoning of the world’s most skilled practitioners.”

Forbes was the first to report on this funding round, and AfterQuery has not yet responded to requests for immediate comments.