Island announced on Thursday that it raised $400 million in a Series F led by Evolution Equity Partners, valuing the enterprise security company at $6.4 billion as businesses deploy more AI agents.
The Dallas-based company’s valuation is more than 30% above the $4.8 billion it reached in a 2025 funding round, according to a Reuters report. Island said its annual recurring revenue has doubled every fiscal year since its launch in 2022.
The round comes as cybersecurity startups raise capital to address the challenge of controlling increasingly autonomous AI systems. Cyera announced a $400 million investment from Goldman Sachs to extend its Series G, while Onyx Security raised $113 million in a Series B in July. Armadin raised $189.9 million across seed and Series A funding in March.
In a statement, Island said it began with its Enterprise Browser and has since expanded into data protection, endpoints, applications, and secure access service edge.
The company now bills itself as the "agentic control plane for enterprises" across browsers, endpoints, networks, and data. The company says its platform gives agents identity management, access guardrails, cost controls, and a full audit trail.
“We’ve entered a new era in which people and AI agents work side by side,” Island CEO Mike Fey said. “Just like humans, agents need the right context, access, guardrails, and accountability to succeed.”
Island CTO Dan Amiga said the system is designed to show “who or what is acting, what it can reach, what data it can use” and whether an action should be allowed.
The company employs 1,000 people. Its existing investors, including Prysm Capital, Sequoia Capital, Coatue Management, Cyberstarts, Insight Partners, and J.P. Morgan Growth Equity Partners, also participated in the Series F, per the statement.