{"page":"/blog/identity-after-privacy-sandbox","modified":"2026-10-18","license":"https://creativecommons.org/licenses/by/4.0/","columns":["Layer","What it does","Build or buy","Where the data sits"],"rows":[["1. First-party graph","Links logins, loyalty IDs, CRM and transactions into one household or person key","Build; see First-party data strategy for publishers","Your warehouse"],["2. Consent and preference store","Records TCF v2.3 strings, GPP sections, preference center choices, with timestamps","Buy a CMP, own the records","Your warehouse, EU-hosted for EU users"],["3. Deterministic ID bridge","Converts hashed email or phone into EUID or UID2 tokens for open-web buying","Private operator","Inside your perimeter; tokens leave, raw hashes do not"],["4. Network and probabilistic reach","Adds telco signals (Utiq) or probabilistic IDs (ID5) for unauthenticated traffic","Buy","Vendor side; pass through user.eids"],["5. Contextual","Classifies pages and content for targeting without a user identifier","Build or buy","Yours or vendor"],["6. Measurement","Server-side event collection, clean-room matching, incrementality","Build the collection, buy the clean room if needed; see Clean room architectures compared","Your warehouse; aggregates to partners"]],"sourceUrls":[[],[],[],[],[],[]]}