Island, which builds a security-hardened "enterprise browser" for corporate employees, announced a $400 million Series F round this week that values the company at $6.4 billion — more than double its $4.8 billion valuation from a March 2025 raise. The round was led by Evolution Equity Partners, with existing backers including Sequoia Capital, Coatue Management and Insight Partners also participating.
Island's pitch is a browser built for the workplace rather than the open web: it gives IT and security teams the ability to control, monitor and restrict how employees handle sensitive data through the browser itself, rather than layering separate security tools on top of Chrome or Safari. "Island created the first Enterprise Browser to protect the primary place people work," said co-founder and chief executive Mike Fey.
Chasing the AI agent boom
The company says it has doubled annual recurring revenue every year since launching in 2022 and now employs roughly 1,000 people, with plans to add hundreds more. Much of the new funding, according to SiliconANGLE, is earmarked for extending Island's control layer to AI agents that now browse and act on behalf of employees inside corporate systems — a fast-growing enterprise security concern as companies deploy more autonomous AI tools with access to internal data.
Cybersecurity entrepreneur Dmitri Alperovitch also made a personal investment in the round, a detail several outlets flagged as a signal of the deal's profile within the security investor community.
The raise lands amid a broader surge of megaround financing for cybersecurity and enterprise-security startups this year, as venture investors bet that AI-driven changes to how employees and software interact will require an entirely new layer of corporate defense. Island's jump to $6.4 billion places it among the more richly valued private security companies to raise this quarter, according to SecurityWeek.
Island has not disclosed a timeline for an IPO. For now, the company says the new capital will fund product expansion rather than acquisitions, as it works to stay ahead of rivals also building security tooling for the agentic-AI era.
