AI
Y Combinator's Fastest-Ever Unicorn: AfterQuery Hits $3.2B Valuation in 18 Months
The AI training-data startup surpassed billion-dollar valuation in record time, less than five months after its Series A round, now backed by major labs including Nvidia.
TechCrunch — AI
AfterQuery, an AI training-data startup, has reportedly secured funding that values the company at $3.2 billion—a milestone reached in just 18 months since its founders entered Y Combinator's Winter 2025 cohort.
Record-Breaking Growth Trajectory#
The valuation represents a stunning expansion: the company reached $300 million in valuation during its Series A announcement in April, and has grown more than 10 times larger in less than five months. Y Combinator partner Gustaf Alströmer confirmed that this marks the fastest journey from launch to unicorn status in the accelerator's history. The founding team, both members in their early twenties, achieved this acceleration while still in their earliest professional years.
Business Model and Customers#
The San Francisco-based startup operates in the AI training space, having reached an annualized revenue run rate of $100 million by spring 2026. Its client roster includes major technology and research organizations such as Nvidia, Legora, and South Korean AI research lab Motif Technologies.
Competitive Positioning#
AfterQuery joins a growing cohort of startups—including companies like Mercor and Scale—that leverage the expertise of professionals in specialized fields such as medicine, law, and other domains. What distinguishes AfterQuery's approach is its focus on training AI models and agents to replicate professional workflows and decision-making patterns. The company aims to encode "the patterns, decisions, and reasoning of the world's best practitioners" into its systems, rather than simply improving factual accuracy in model outputs.
