Build a first-party audience segment in DV360 using the Audience API

Steps

1. Use the Display & Video 360 REST API firstAndThirdPartyAudiences resource to create a new first-party audience; set the audienceType to FIRST_PARTY and define the audienceSource (e.g., YOUTUBE, GOOGLE_ANALYTICS, or PIXEL).
2. For pixel-based audiences, reference the Floodlight activity tag or Google tag that fires on the relevant conversion or page-visit event.
3. Set the membership duration (membershipDurationDays) to specify how long a user remains in the audience after qualifying; the maximum supported duration is 540 days.
4. Link the audience to a line item's audienceTargetingConfig by including the audience segment ID in the includedFirstAndThirdPartyAudienceGroups field.
5. Allow 24–48 hours for the audience to populate before expecting targeting to take effect; newly created segments start with zero members and will not serve until the minimum size threshold is reached.
6. Use the audienceGroups structure to combine multiple segments with AND or OR logic; AND (intersection) logic requires all segments to be in the same group, while OR (union) logic uses separate groups.