First-party signals are information a business collects directly from its interactions with customers, such as purchases, sign-ups, or repeat visits. In marketing systems, these events can help measure conversions and inform advertising decisions.
Because these signals may include identifiers or sensitive details, they need careful handling. In real-world ad technology, businesses may send conversion events from customer-management or ecommerce systems to advertising platforms, directly or through an integration layer. Defenses include limiting access to the data, validating event fields and destinations, respecting consent, and monitoring for accidental or unauthorized sharing.