Snorkel AI raised $350 million in a Series E round at a $3.5 billion valuation, the company said in a post on X. Insight Partners and S32 co-led the round, with significant participation from existing investor Addition.
The company said it surpassed $375 million in annualized recurring revenue and grew more than 18x in under a year. CEO Alex Ratner said the company crossed that annualized revenue run rate this week, nearly a year after launching its data-as-a-service offering.
The funding follows Snorkel's shift from data-labeling automation software to a data-as-a-service model. It supplies finished datasets and reinforcement-learning environments to customers, including for coding data.
New investors in the round include March Capital, Blumberg Capital, Allegis Capital, Frontline, Standard and Third Point Ventures. Existing investors Greylock, Lightspeed, GV, Factory, Prosperity7, Walden Catalyst and Wells Fargo also participated.
Insight Partners Managing Director Lonne Jaffe said Snorkel's "research-grade approach to AI data, environments, and measurement is becoming an increasingly important ingredient in building capable and reliable AI systems." S32 CEO and General Partner Andy Harrison said Snorkel's "expert-agentic environments create a unique flywheel between human expertise and AI, delivering data at the speed and quality that enables a new era of efficiency and accuracy for model development."
The Series E follows a $100 million Series D announced in May 2025 at a $1.3 billion valuation, making the new valuation roughly a tripling. Snorkel AI was founded in 2019 by a team spun out of the Stanford AI Lab.
