AI training-data startup AfterQuery has reportedly raised a round valuing the company at $3.2 billion, according to Forbes, just five months after it announced a $30 million Series A at a $300 million valuation in April. The jump represents more than a tenfold increase in under half a year, which Y Combinator partner Gustaf Alströmer said marks the fastest path from launch to unicorn status in the accelerator’s history. AfterQuery’s founders, now 22 and 23 years old, joined Y Combinator’s Winter 2025 cohort roughly 18 months ago.
In April, the San Francisco-based company said it had reached an annualized revenue run rate of $100 million and named clients including Nvidia, Legora, and Korean AI lab Motif Technologies.
AfterQuery is part of a growing wave of startups, following firms like Mercor and Scale, that employ knowledge professionals such as doctors and lawyers to support AI model training. Rather than focusing on answer accuracy alone, the company said its approach centers on training models and agents to replicate how professionals reason through and complete tasks, describing its method as capturing the decision-making patterns of top practitioners in various fields.
Featured image: Credit: AfterQuery