Snorkel AI Raises $350M Series E at $3.5B Valuation

On September 22, Snorkel AI founder Alex Ratner announced a $350M Series E at a $3.5B valuation, co-led by Insight Partners and S32. The round nearly triples the company's $1.3B Series D valuation from 17 months earlier, backed by Data-as-a-Service revenue growing over 18x in 12 months and an ARR run-rate above $375M, underscoring strong investor demand for high-quality training data businesses.

Confirmed

$350M Series E at a $3.5B valuation, co-led by Insight Partners and S32
Existing investors Addition, Lightspeed, Greylock, GV, and Wells Fargo participated; per an Insight Partners post shared by Ratner, Third Point, March, Blumberg, Allegis, Standard VC, and Frontline also joined, with Insight framing the bet as professional "Data 2.0" data factories
Per TechCrunch coverage relayed by Ratner, the valuation is nearly 3x the $1.3B Series D from 17 months prior; TechCrunch describes Snorkel as a startup helping AI labs and enterprises build training datasets and simulation environments
Data-as-a-Service has grown over 18x in the past 12 months, with ARR run-rate surpassing $375M
Founded in 2019 by a Stanford team including Alex Ratner; GV and Greylock were earliest investors, with Greylock leading the seed and Series A and GV and Greylock leading the first round about 7.5 years ago
Investor Blumberg Capital positions the company as a "frontier AI data lab" building data and training environments for advanced AI systems

Why it matters

Snorkel's data-centric approach won a premium from capital markets, and the $3.5B valuation relative to revenue signals strong demand for high-quality training data businesses
The 18x+ one-year growth of Data-as-a-Service underpins the valuation and signals enterprise AI competition shifting from the model layer to the data layer

2026-09-22 ~ 2026-09-24 · 15 related posts

Primary sources

Snorkel AI raises $350M Series E at $3.5B valuation, passes $375M ARR — ajratner · 2026-09-22 23:12 (UTC+08:00)
Snorkel AI raises $350M Series E at $3.5B valuation, tops $375M ARR — ajratner · 2026-09-22 23:12 (UTC+08:00)
Snorkel AI raises $350M at $3.5B valuation as AI training data demand booms — ajratner · 2026-09-23 14:50 (UTC+08:00)

[source] Snorkel AI raises $350M Series E at $3.5B valuation, passes $375M ARR — ajratner · 2026-09-22
Snorkel AI raises $350M at $3.5B valuation as ARR grows 18x in under a year — ajratner · 2026-09-23
Snorkel AI raises $350M Series E to build the data factory for "Data 2.0" — ajratner · 2026-09-23

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