Snorkel AI nearly triples its valuation to $3.5 billion as labs pay heavily for training data

Snorkel AI, which helps AI labs and corporations build training datasets and simulated environments, has raised a $350 million Series E at a $3.5 billion valuation. Insight Partners and S32 led the round. Existing investors including Addition, Lightspeed, Greylock, GV and Wells Fargo also took part. The valuation is nearly triple the $1.3 billion the seven-year-old company reached when it raised a $100 million Series D 17 months ago. Snorkel began by selling software to automate data labeling. Last year it shifted to delivering completed datasets, an offering it calls data-as-a-service. It uses a hybrid approach: its own software and models generate synthetic data alongside work by subject-matter experts. The company says its annualized revenue run rate is now $375 million, up eighteenfold over the past 12 months. TechCrunch attributes the growth to AI labs' demand for high-end training data and points to similar gains elsewhere. Mercor's gross annualized revenue has reached $2 billion, Handshake passed $1 billion earlier this year, and Micro1 has scaled to $500 million. These companies pay roughly 60 to 70 percent of their top-line income to the domain specialists who do the work. The funding shows that investors expect the training-data supply chain to become a large business alongside the model makers.