Glossary
Third-Party Cookie
A cookie set by a domain different from the website the user is visiting.
Identity & Data InfrastructureFoundationSource: Industry consensus
Definition
A cookie set by a domain different from the website the user is visiting.
Why it matters
Third-party cookie deprecation is the single biggest reason identity resolution, clean rooms and universal IDs have all become load-bearing infrastructure.
Related terms
Practitioner notes
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