Privacy-Enhanced Cross-Media Measurement: How Fifty5Blue (formerly Kantar Media) Leveraged AWS Clean Rooms to Establish Audit Transparency During Panel Data Exchange

This article describes how Fifty5Blue (formerly Kantar Media) used AWS Clean Rooms to enable secure cross-media measurement data exchange with publishers while maintaining privacy and audit compliance.

• AWS Clean Rooms enables private set intersection for matching users across datasets without exposing raw data
• Fifty5Blue's encrypted data stored in publisher S3 buckets, protected by Fifty5Blue-owned KMS keys
• Third-party auditors can verify compliance without accessing unencrypted panelist membership data
• Solution replaced expensive homomorphic encryption approach, reducing setup time from weeks to days
• AWS CloudTrail and S3 versioning create verifiable audit trails for accountability
• Analysis rules enforce fine-grained privacy controls on permitted data analysis types
• Significantly faster processing: hours instead of 10-12 hours for daily data exchanges

AWS Clean Rooms provides a scalable, cost-effective solution for privacy-preserving data collaboration in digital advertising measurement.