POLICY ZONES: HOW META ENFORCES PURPOSE LIMITATION AT SCALE IN BATCH PROCESSING SYSTEMS

Summary from the TLDR Web Dev newsletter

Meta developed Privacy Aware Infrastructure (PAI) and Policy Zones to enforce purpose limitations on data in large-scale batch processing systems. Policy Zones uses runtime enforcement and SQL parsing to track and control data flow across Meta's data warehouse, integrating with millions of data flows daily and performing trillions of user consent checks per hour. Meta provides tools like Policy Zones Manager (PZM) to help engineers use Policy Zones.