Snorkel AI raises $350M Series E at $3.5B as 'data-as-a-service' for frontier labs passes a $375M run rate
On Sept 22, 2026 Snorkel AI announced a $350M Series E at a $3.5B valuation, led by Insight Partners and S32. That is nearly triple its May 2025 price. Its expert "data-as-a-service" business, which sells finished training datasets, evaluation data and RL environments to frontier labs, grew more than 18x in about a year to an annualized revenue run rate above $375M.
Key facts
- Series E: $350M at $3.5B; led by Insight and S32; with Third Point, March, Blumberg, Allegis, Standard VC, Frontline and existing investors Addition, Lightspeed, Greylock, GV and others (Snorkel)
- Data-as-a-service launched ~Sept 2025; grown 18x+; run rate crossed $375M the week of the announcement (CEO Alex Ratner, Snorkel blog)
- Previous round: $100M Series D at $1.3B (May 2025)
- Ratner calls it 'Data 2.0': frontier training data has become 'too hard for even the smartest human experts to do alone', so humans and AI agents build it together
What happened
Snorkel started as a Stanford weak-supervision project that sold labeling software. It now supplies finished expert datasets and RL environments directly to labs, and raised $350M on the strength of that business.
Why it matters
It shows how much frontier labs spend on expert-built data and RL environments, a market also served by Scale, Surge, Mercor and others.
Changelog
- 2026-10-01: created from leads
Sources (3)
- officialSnorkel AI blog (Alex Ratner): Data 2.0 and the research era of AI data
- pressTechstrong.ai: Snorkel AI secures $350M for more complex AI training and evaluation data
- pressTech Funding News: Insight Partners, S32 back Snorkel AI at $3.5B valuation
id: 2026-09-22-snorkel-ai-350m-series-e · updated 2026-10-01 · open in the interactive timeline