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Identity & Data · DCR

Data Clean Rooms

A data clean room is a secure, privacy-controlled environment where two parties can match and analyze their data together without either exposing raw, user-level records to the other.

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

Key takeaways

  • A clean room lets two parties combine data without sharing raw user records.
  • Only aggregated, privacy-safe outputs leave the environment.
  • It's used for measurement, audience overlap, and activation after cookie loss.
  • Walled gardens and CTV publishers use clean rooms extensively.

How clean rooms work

Each party uploads data into a governed environment that permits matching and analysis "” say, overlapping a brand's customers with a publisher's audience "” but restricts outputs to aggregated results. Neither side sees the other's raw records, which lets sensitive first-party data be joined within privacy constraints.

Why they matter now

As third-party identifiers disappear, clean rooms became the primary way to connect a brand's first-party data with a publisher's audience for targeting and measurement. They are central to how walled gardens and CTV platforms let advertisers use their own data without releasing user-level information.

At a glance
PurposePrivacy-safe data collaboration
InputsTwo parties' first-party data
OutputsAggregated, non-identifying results
Common usersWalled gardens, CTV publishers, brands

Frequently asked questions

What is a data clean room used for?

For measurement, audience overlap analysis, and building targetable audiences by matching two parties' first-party data without either exposing raw user-level records.

Why are clean rooms important after cookie deprecation?

Because they let brands and publishers connect their first-party data for targeting and measurement without third-party cookies or sharing sensitive raw data.