Island raises $400 million at $6.4 billion valuation as AI agents reshape enterprise security
The cybersecurity company is moving beyond its enterprise browser to build a broader control layer for employees and AI agents operating across corporate systems.
Cybersecurity company Island has raised $400 million at a $6.4 billion valuation, more than doubling its valuation since 2024 as it seeks to expand from securing the enterprise browser into a broader control layer for the growing number of AI agents operating inside companies.
The Series F round was led by Evolution Equity Partners and included both existing and new investors. Island said the funding will support its next phase of growth as enterprises deploy AI agents that can interact with applications, data and corporate systems with increasing independence.
The financing marks a significant evolution for a company that helped establish the enterprise browser as a new category of enterprise security software. Island now wants to apply the same basic idea beyond the browser, giving companies a way to see, control and audit what both employees and AI agents are doing across devices, applications, networks and data.
“Agents do not operate in a single layer of the technology stack, so they cannot be governed from one,” Dan Amiga, Island's co-founder and CTO, said.
Island's answer is what it calls an “agentic control plane,” which brings together controls for the endpoint, network, data, identity and observability. The goal is to give companies a single view of who or what is acting, what it can access, what data it can use and whether an action should be permitted.
Founded by Amiga and CEO Mike Fey, Island emerged from stealth in 2022 with an enterprise browser designed to put security, IT controls and productivity tools directly into the browser used by employees. The company raised $250 million at a $4.8 billion valuation in March 2025, after a $175 million round in 2024 valued it at $3 billion.
By September 2026, Island had reached approximately $200 million in revenue and was growing at about 100% annually. The company said eight of the world's 10 largest banks were using its enterprise browser.
Island now employs 1,000 people, according to the company, compared with more than 500 last year. Its annual recurring revenue has doubled in every fiscal year since its launch, the company said.
Island has expanded from its enterprise browser into consumer browsers through an extension, endpoints, applications, modern SASE architecture and data protection. It says the combination allows organizations to apply one policy engine and one audit trail across the chain of human and agentic work.
That includes identity governance, access controls, guardrails, data boundaries, human approvals and cost controls.
“Just like humans, agents need the right context, access, guardrails, and accountability to succeed,” Fey said.
Island's existing investors participating in the new round include Prysm Capital, Sequoia Capital, Coatue Management, Cyberstarts, Insight Partners, J.P. Morgan Growth Equity Partners, Alta Park Capital, Georgian, G Squared and Squarepoint. Dmitri Alperovitch, the cybersecurity entrepreneur and former CrowdStrike CTO, also made another personal investment.
