Mercor Hits $20B Valuation After $750M Series D to Train and Test AI Agents

AI training startup Mercor has secured $750 million in a Series D funding round that values the company at $20 billion, the firm said on Tuesday. Benchmark, Felicis, Fundomo, Nvidia and funds managed by affiliates of Apollo were among the participants.

The San Francisco-based company started out as an AI-powered hiring platform but now connects technology companies with subject-matter experts whose knowledge is used to train, test and improve AI models and agents. Mercor said the new capital will go towards training and testing AI agents on professional tasks.

Co-CEO Brendan Foody said every job in the economy will require its own AI agents, and every company will need a way to train and evaluate those agents on its own work.

The latest valuation roughly doubles the approximately $10 billion figure Mercor reached after raising $350 million in October last year. The company counts Jack Dorsey and venture capitalist Peter Thiel among its backers.

The deal reflects strong investor appetite for AI, which has driven a sharp rise in private funding this year and produced a growing group of heavily capitalised startups with multibillion-dollar valuations. According to Crunchbase, AI-driven startups raised $102 billion in the third quarter of 2026, accounting for 64% of global venture capital.