AI training-data startup AfterQuery has reportedly reached a $3.2 billion valuation after a new funding round, marking a dramatic jump from its $300 million valuation in April.
The company's rise has been described by Y Combinator partner Gustaf Alströmer as the fastest path from launch to unicorn status in the accelerator's history. AfterQuery joined Y Combinator's Winter 2025 cohort just 18 months ago, and its founders are now 22 and 23 years old.
Based in San Francisco, the startup said in April that it had reached an annualized revenue run rate of $100 million and was working with major AI labs and technology companies, including Nvidia, Legora and Motif Technologies.
AfterQuery belongs to a growing group of startups that use expert knowledge professionals such as doctors and lawyers to help train AI systems. Its approach focuses not only on accuracy, but on teaching models and agents to work with the judgment, methods and reasoning patterns of top practitioners.
This rapid expansion highlights how specialized AI infrastructure is becoming a central layer of the next generation of intelligent systems, with broad implications for how digital work may be built in the future.
