Glossary · Analytics & web
Third-party cookies
A third-party cookie is set by a domain other than the one the user is visiting — typically an ad or analytics vendor embedded via script — letting that vendor recognize the same browser across unrelated sites.
A first-party cookie is set by the site in the address bar and is only ever sent back to that site — a shopping cart or login session, for example. A third-party cookie is set by an embedded resource (an ad tag, a tracking pixel, a "Like" button) on a domain the user never typed into their address bar. Because that same embedded resource appears on thousands of unrelated sites, the vendor can correlate one browser’s visits across all of them, which is the technical basis for cross-site ad retargeting and behavioral profiling.
This is also why third-party cookies attract the most regulatory and browser scrutiny: the user has no direct relationship with the domain doing the tracking, and rarely knows it is happening. Major browsers now block or restrict third-party cookies by default, which has pushed both advertising and analytics vendors toward alternatives — some privacy-preserving (aggregation, on-device processing), others simply harder to see, like fingerprinting.
Ciphera Pulse sets no cookies at all, first-party or third-party — there is no cross-site identifier for Pulse to correlate in the first place.