AI data company Mercor completes $750 million Series D funding

AI data company Mercor has closed a $750 million Series D at a $20 billion valuation, with participation from Benchmark, General Catalyst, NVIDIA, Salesforce and Zoom, alongside a tender offer for employee shares. The round marks one of the largest private raises for an AI data and evaluation provider, underscoring investor appetite for companies that supply the human feedback and assessment pipelines used to train and fine-tune models. Mercor builds custom AI evaluations with enterprises and domain experts based on real-world workflows, and said it will direct the new capital toward evaluations, post-training infrastructure and research, plus environments where agents can learn complex workflows. The deal also highlights NVIDIA's and Salesforce's continued push into the data layer of the AI stack rather than only model development. What to watch next is how quickly Mercor converts its $20 billion valuation into enterprise contracts and whether the post-training and agent-training market attracts further large rounds from rivals.