Third-Party Cookie
A third-party cookie is set by a domain other than the one a user is visiting, typically by ad and tracking services embedded in a page. It enabled cross-site tracking and targeting, and it is being restricted or blocked by major browsers over privacy concerns.
Third-party cookies let companies follow users across unrelated sites to build behavioral profiles for advertising. That cross-site tracking is exactly what privacy efforts target.
Safari and Firefox block them by default, and the broader industry is shifting toward first-party data, contextual targeting, and privacy-preserving alternatives.
Go deeper
6 min readWhy Third-Party Cookies Are Going Away (and What to Do Next)Third-party cookies and cross-site tracking are being dismantled by browsers and regulators. Here is what is changing, why, and how to prepare with first-party data.11 min readFirst-Party vs Third-Party Data: The Complete ComparisonFirst-party data is the customer data you own. Third-party data is bought from outside sources. Here is how they differ on ownership, accuracy, cost, privacy, and risk, and which to rely on now.
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