AfterQuery, an AI training-data startup, has secured a significant funding round that catapults its valuation to $3.2 billion, just five months after announcing a Series A round worth $30 million at a $300 million valuation in April.

This meteoric rise represents a staggering 10x increase in less than half a year, with Gustaf Alströmer, Y Combinator partner, describing it as the fastest ascent to unicorn status in the accelerator's history. The 22- and 23-year-old founders of AfterQuery, who joined Y Combinator's Winter 2025 cohort just 18 months ago, have now achieved unprecedented success.

April, afterquery revealed annualized revenue

In April, AfterQuery revealed an annualized revenue run rate of $100 million, highlighting its rapid growth and partnerships with prominent labs, including Nvidia, Legora, and Motif Technologies. The company's customer list boasts several of the biggest names in AI research.

AfterQuery is part of a growing wave of startups leveraging knowledge professionals to train models and agents. However, unlike traditional approaches that focus on accuracy, AfterQuery focuses on encoding the patterns, decisions, and reasoning of world-class practitioners. This innovative approach has garnered significant attention from investors and experts alike.

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The news was first As the startup community converges to address a pivotal question – how to build sustainably in the AI era – AfterQuery's remarkable story serves as a reminder of the rapid evolution of this technology.

Y Combinator

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AfterQuery Becomes Y

Motif Technologies

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Winter 2025

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