Sublime Security Raises $150 Million for Email Security Platform

According to SecurityWeek, Sublime Security announced on 28 October 2025 that it has raised $150 million in a Series C funding round, bringing the total raised by the company to more than $240 million. The Series C round was led by Georgian, with participation from Avenir, 01A, Index Ventures, IVP, Citi Ventures, and Slow Ventures, and the new investment will fuel product development and global expansion.

Sublime has developed an agentic email security platform that uses AI agents to analyse messages, with a distributed detection model conducting intent and behavioural analysis alongside deep content inspection. The platform can automate workflows, with the Autonomous Security Agent (ASA) triaging threats and the Autonomous Detection Engineer (ADÉ) deploying tailored defenses to protect against new threats.

Sublime says its platform is already used by major companies such as Spotify, Snowflake, Zscaler, Anduril, Elastic, SentinelOne and Compass. The funding follows a December 2024 round in which Sublime raised $60 million, and the company aims to extend its autonomous defence capabilities to security teams at scale.