Snorkel AI raises $350M Series E at $3.5B valuation
Original: Snorkel AI triples valuation to $3.5B as demand for AI training data booms
Why This Matters
Valuation tripling in 17 months signals how urgently frontier AI labs need high-quality training data at scale.
Snorkel AI, a training data and RL environment provider, closed a $350M Series E led by Insight Partners and S32, tripling its valuation from $1.3B to $3.5B in 17 months. The company reported an annualized revenue run rate of $375M — an 18x increase over 12 months.
Snorkel AI, founded in 2019 by Stanford AI lab researcher Alex Ratner, has raised $350 million in a Series E round led by Insight Partners and S32. The deal values the company at $3.5 billion, nearly triple the $1.3 billion valuation it carried when it raised $100 million in a Series D just 17 months ago. Existing backers — Addition, Lightspeed, Greylock, GV, and Wells Fargo — all returned for the new round.
The company says its annualized revenue run rate has hit $375 million, an 18x jump over the past year. Originally a data-labeling automation software vendor, Snorkel pivoted last year toward delivering completed datasets directly — what it calls data-as-a-service. Unlike competitors that function primarily as human expert marketplaces, Snorkel takes a hybrid approach: synthetic data generation via its own models, combined with domain specialists.
Because Snorkel sells finished datasets and RL environments rather than raw labor hours, payments to human experts flow through cost of goods sold rather than inflating top-line revenue figures. That's a meaningful distinction from peers like Mercor ($2B gross annualized revenue), Handshake ($1B), and Micro1 ($500M), whose headline numbers include 60–70% payouts directly to contracted specialists.