Definition
Five Eyes (FVEY) is the oldest and tightest of the Western intelligence alliances, originating in the 1946 UKUSA Agreement between the UK and US and later expanded to include Canada, Australia, and New Zealand. Member agencies — NSA, GCHQ, CSE, ASD, and GCSB — share signals intelligence freely with one another, including, in some accounts, intelligence collected on each other's citizens to bypass domestic legal restrictions on surveillance.
Nine Eyes and Fourteen Eyes
Two extended alliances are commonly cited. Nine Eyes adds Denmark, France, the Netherlands, and Norway. Fourteen Eyes (also called SIGINT Seniors Europe) adds Germany, Belgium, Italy, Spain, and Sweden. These expansions involve narrower scopes of cooperation than the core Five Eyes arrangement, but they are mentioned in VPN marketing as jurisdictions where data demands are likely to be honoured and shared widely.
Why VPN Buyers Care
A VPN provider headquartered in a Five Eyes country may be compelled by law to assist intelligence agencies, possibly with a gag order preventing them from informing users. Providers who explicitly position themselves outside these alliances — Mullvad in Sweden (Fourteen Eyes), Proton in Switzerland (not in any Eyes), IVPN in Gibraltar, ExpressVPN in the British Virgin Islands (a British Overseas Territory with its own laws) — make their jurisdiction a marketing centerpiece. The argument is partly substantive and partly symbolic: the strongest practical defence is no-logs architecture, since a provider with nothing to hand over cannot be coerced into handing it over regardless of jurisdiction.