Ask What signal would you trust most to attribute a display ad conversion correctly in a cookieless setup?

[Dean101]

The strongest signal is a first-party, authenticated identifier passed through a server-side conversion event, especially when a logged-in user ID or hashed email can be matched to the ad click. This avoids reliance on third-party cookies and reduces noise from probabilistic modeling. By stitching click IDs from the ad request with backend purchase events, you get a clear, consent-based path from impression to conversion. Monitoring server logs and deduplicated events also reveals where attribution breaks or inflates. Over time, combining this with aggregate cohort trends improves confidence in measurement.