Why it exists
After Apple's App Tracking Transparency, Meta cannot track opted-out iOS users the old way. AEM reports their conversions in aggregate, with privacy protections such as removing identifiers and adding differential privacy.
What changed
AEM used to cap each verified domain at eight conversion events, ranked by priority in an Events Manager tab. Meta has removed that: you no longer prioritize eight events, the AEM tab is gone, domain verification is no longer needed for event configuration, and you do not pick a conversion domain when you build a campaign. Eligible events are processed automatically.
What still matters
With no ranking step, the lever is signal quality: send the events that reflect real value, like purchase or qualified lead, and send them reliably. That is why server-side tracking and strong event match quality matter more than ever.
Common questions
What is Aggregated Event Measurement?
Meta's privacy-compliant way to measure web and app conversions from people on iOS 14 and later who opted out of tracking, reporting them in aggregate.
Do I still need to rank eight events in Aggregated Event Measurement?
No. Meta removed the eight-event limit per domain and manual event prioritization, along with the AEM tab in Events Manager. Eligible website events are now processed automatically, so the work shifts to sending accurate, high-value events through the pixel and Conversions API.