Snorkel AI has raised $350 million in a Series E that lifts its valuation to $3.5 billion, giving the company a large infusion of capital to expand its data-as-a-service offering as demand for AI training data grows.

The round comes as organisations building machine learning models shop for more and better labelled data and services that accelerate model training. Snorkel, a seven-year-old startup, intends to use the new funding to fuel its data-as-a-service approach, a strategy that packages curated, labelled datasets and pipelines and sells them as a service rather than delivering bespoke consulting engagements.

A jump in valuation of this size signals investor willingness to pay a premium for companies positioned in the AI training-data market. For Snorkel, the E provides resources to hire, invest in engineering and scale commercial operations, and to move faster on product development tied to its platform and dataset.

For customers, more capital behind a data-as-a-service vendor can mean faster delivery of production-ready datasets, broader catalogue coverage and deeper tooling for integrating training data into model pipelines. For competitors, the funding round raises the bar for sales and product investment required to keep pace in a crowded market for model training resources.

Snorkel’s financing also highlights broader momentum in the AI ecosystem, where demand for labelled and structured training data has become a critical for many projects. The company’s fresh capital positions it to expand capacity and, while testing whether the market for packaged training data can sustain elevated valuations and rapid scaling.

With the Series E closed, Snorkel’s near-term task is execution: converting capital into product improvements, customer growth and operational scale to justify the higher valuation and to capitalise on the prevailing appetite for AI training data.