Cybersecurity Startup Island Raises $400 Million as AI Risks Fuel Investor Frenzy

Island has raised $400 million in a Series F funding round that values the enterprise cybersecurity startup at $6.4 billion, as companies increasingly deploy AI agents and rethink how employees and automated systems access corporate applications and data.

The financing, announced Thursday, was led by Evolution Equity Partners and included both existing investors and new backers, including Prysm Capital, Sequoia Capital, Coatue Management, Cyberstarts, Insight Partners, J.P. Morgan Growth Equity Partners, Alta Park Capital, Georgian, G Squared and Squarepoint.

Cybersecurity entrepreneur Dmitri Alperovitch also made another personal investment in the company.

Island said the new capital will support product development and international expansion as enterprises adopt AI agents and look for ways to secure and monitor increasingly automated workflows.

The latest valuation is more than double Island’s valuation in 2024, underscoring investor appetite for cybersecurity companies positioned to address the risks emerging alongside the rapid adoption of AI.

"Enterprises are rethinking the basic architecture of work. Island meets the moment with a unique advantage: it can see and govern what people and agents are doing as they interact with applications and data, wherever that happens," said Richard Seewald, founder and managing partner at Evolution Equity Partners.

AI Agents Create A New Security Challenge

Island, founded in 2022, is positioning its enterprise browser and security platform around a workplace where AI agents increasingly operate alongside human employees. Those agents can interact with business applications, corporate networks and sensitive data, creating new security and governance challenges for companies.

"We’ve entered a new era in which people and AI agents work side by side. This investment gives us even more capacity to innovate with our customers and help them safely scale AI," said Mike Fey, Island’s CEO and co-founder.

Island has about 1,000 employees and its annual recurring revenue has doubled each fiscal year since its launch. The company attributed that growth to accelerating enterprise AI adoption and demand for simpler security infrastructure that can protect sensitive data without creating additional friction for employees.

Gili Raanan, founder and general partner at Cyberstarts, said the company’s growth and $6.4 billion valuation reflect demand for security infrastructure built for what it called the "agentic era."

Island Bets On A Broader Security Control Layer

Island says its platform is designed to govern both human users and AI agents across multiple parts of an enterprise technology environment.

"Agents do not operate in a single layer of the technology stack, so they cannot be governed from one," Dan Amiga, Island’s CTO and co-founder, said. He said the company’s control plane brings together "last-mile control, network, data, identity, and observability."

Alperovitch said the rise of AI agents could force companies to reconsider security models built around traditional networks.

"AI agents will break many of the assumptions that have supported network-based security for decades," he said. "Island was built for that shift, giving enterprises full visibility and control without slowing AI down."

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