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A cross-cutting capability used across the buy and sell sides, rather than a single point in the auction chain.
Identity & Data · 1PD

First-Party Data

First-party data is information a company collects directly from its own customers and audiences "” purchases, site and app behavior, subscriptions, and consented profiles "” and owns outright.

Updated 2025-07-06 Author Luc Dumont Reading time ~4 min

Key takeaways

  • First-party data is collected directly from a company's own customers and users.
  • It is owned, consented, and not dependent on third-party cookies.
  • It became the most durable targeting asset after cookie deprecation.
  • It is activated through CDPs, clean rooms, and deterministic IDs like UID2.

Why first-party data won

As third-party signals eroded, the data a company gathers from its own relationships "” logged-in behavior, transactions, loyalty "” became the most reliable foundation for targeting and measurement, because it doesn't depend on cross-site tracking and comes with a direct consent relationship.

First, second, and third-party

First-party data is yours, collected directly. Second-party data is someone else's first-party data shared through a partnership. Third-party data is aggregated and sold by parties with no direct user relationship "” the category most damaged by cookie loss.

At a glance
SourceYour own customers and audiences
OwnershipOwned, consented
DurabilityHigh "” no third-party dependency
ActivationCDP, clean rooms, UID2

Frequently asked questions

What is the difference between first-, second-, and third-party data?

First-party is collected directly by you; second-party is another company's first-party data shared with you; third-party is aggregated and sold by firms with no direct relationship to the user.

Why is first-party data so valuable now?

Because it survives cookie deprecation. It's owned, consented, and independent of cross-site tracking, making it the most durable basis for targeting, personalization, and measurement.