Issue

An Engage audience linked to DV350 is syncing successfully, and the audience was created in the destination. However, the audience size is <1000 when it should be bigger based on Engage audience counts.

Product

Twilio Segment 

Environment

Segment Console

Cause

DV360 requires the following profile identifiers to sync downstream:

• Identifiers required (one of the following):
  • idfa (iOS)
  • advertisingId (Android)
  • anonymousId (Web)

These IDs need to be part of the ID resolution rules and collected by the sources added as Profile Sources in the space:

• To use DV360 with web traffic, you must collect anonymous_id through the client-side analytics.js source.
• To use DV360 with mobile traffic, you must collect IDFAs through Segment’s mobile sources.

If not all profiles in the audience have at least one of these identifiers, then it is expected for the audience to not match the size in Engage.

Additionally, Engage will only include the anonymousId identifier in the payloads sent downstream if the audience has the "Include Anonymous users" flag enabled.

Resolution

Our analytics.js library automatically assigns anonymousId, and our mobile libraries collect automatically collect the device information as well. However, these identifiers need to be configured in the Identity Resolution Rules of the space, and the sources need to be connected as Profile Sources.

It is not possible to edit an existing audience to include anonymous users. If your current audience does not have the "Include Anonymous users" flag enabled, a new one needs to be created.

Additional Information 

When you first preview and create an audience in Engage, the audience may contain many audience members. This is more likely if you select the Historical Backfill option. This does not reflect the audience that syncs to DV360 for the following reasons:

1. During an audience sync, Segment sends a list of anonymousId values to Google. Google attempts to match those values in their match table, to find an associated google_user_id.
2. To complete this lookup, Google must have both the anonymousId and have it store along side a matched google_user_id. This occurs when a user visits your website with both the Doubleclick Floodlight tag installed, and the DV360 integration completed.

As a result, you must have Doubleclick Floodlight and the DV360 integration in place before Google can match users and make them available for retargeting.

To help reduce the difference between Engage and DV360 audience sizes, Segment recommends that you deselect the Historical Backfill option when you create the audience that syncs to DV360.