AfterQuery hits $3.2 billion valuation in Y Combinator’s fastest unicorn run
The AI model-training startup has seen its valuation jump more than 10x in five months, cementing its status as the accelerator’s quickest path to unicorn status.
AI model-training startup AfterQuery has reportedly raised a new funding round that values the company at $3.2 billion. The valuation represents a more than 10x increase from the $300 million mark set during its $30 million Series A announcement in April. According to Y Combinator partner Gustaf Alströmer, this rapid ascent makes AfterQuery the fastest startup in the accelerator’s history to achieve unicorn status.
The San Francisco-based company was founded by two graduates of Y Combinator’s Winter 2025 cohort, who are currently 22 and 23 years old. Their participation in the programme concluded just 18 months ago. In April, the startup disclosed that it had reached an annualised revenue run rate of $100 million while working with several major AI labs.
AfterQuery distinguishes itself by employing knowledge professionals, including doctors and lawyers, to train AI models. Unlike competitors such as Mercor and Scale, which often focus on question accuracy, AfterQuery trains models and agents to execute professional tasks. The company describes its approach as encoding the patterns, decisions, and reasoning of the world’s best practitioners.
The startup has named Nvidia, Legora, and the Korean AI lab Motif Technologies as customers. This client base underscores the company’s integration into the broader AI infrastructure ecosystem. The funding round was first reported by Forbes, though AfterQuery could not be immediately reached for comment.
The specific amount of capital raised in this latest round has not been disclosed. However, the valuation surge highlights the intense competition for high-quality training data in the artificial intelligence sector. Investors appear willing to pay a premium for startups that can bridge the gap between raw model capabilities and professional-grade task execution.
This development positions AfterQuery as a key player in the emerging market for AI training data. As the industry moves beyond basic language processing, the ability to replicate professional reasoning is becoming a critical differentiator for model performance.
