Enterprise browser maker Island has closed a $400M Series F round that values the company at $6.4B.
Evolution Equity Partners led the raise, announced Thursday, taking Island’s total funding past $1B since its launch in 2020. The company said the money will go toward platform development and growth.
Island started with a hardened browser and has widened into an agentic control plane meant to govern both human activity and automated workflows across endpoints, software and networks.
The platform now applies an endpoint-outward SASE architecture, delivering zero trust network access, device posture checks and inline data loss prevention without a traditional VPN. Security teams can set granular DLP rules where work happens, blocking unapproved clipboard transfers, downloads and screen captures.
For AI workloads, Island adds guardrails that keep proprietary material away from outside language models while reducing prompt injection exposure. The company argues that agentic tools need the same governance as staff, with policy applied at the point of use rather than bolted on afterwards.
The round lands as investors keep funding browser and identity-layer security, betting that controlling the endpoint session is cheaper than chasing individual threats after they land.
