Snorkel AI Raises $350M Series E at $3.5B Valuation as Data Demand Surges

Snorkel AI raised a $350 million Series E at a $3.5 billion valuation, nearly tripling its value from a $1.3 billion valuation 17 months ago. The round was led by Insight Partners and S32, with participation from Addition, Lightspeed, Greylock, GV, and Wells Fargo. The seven-year-old startup, which shifted last year from data-labeling software to selling completed data sets, reports annualized revenue of $375 million, an 18-fold increase over 12 months. AI labs' demand for premium training data is driving growth across the sector. Rivals Mercor, Handshake, and Micro1 have reached gross annualized revenues of $2 billion, $1 billion, and $500 million, respectively. Snorkel says its human-expert payments are booked as cost of goods sold rather than headline revenue, since it sells reinforcement learning environments and datasets rather than labor.