User Profile Merge Logic

How Personalization merges two or more user profiles depends on whether or not those profiles share identity types.

When Merging Occurs	When Merging Doesn’t Occur
When Personalization merges two or more user profiles, it stores all historic events, transactions, and interactions for those user profiles based on the following logic: If an identity type exists for only one user profile, Personalization retains that identity type and adds it to the merged user profile. If an identity type exists in more than one user profile, Personalization retains the identity type with the latest timestamp and adds it to the merged user profile. If metadata doesn’t exist or doesn't have a timestamp, Personalization uses the system updated timestamp instead.	If there isn't shared identity type data between the user profiles, Personalization doesn’t forcefully merge them. For example, Personalization doesn’t perform a request to rename, or merge, LoyaltyID 123 to LoyaltyID 567 if there's no shared identity type data between the two user profiles. Even when there’s a matching identity attribute, Personalization doesn’t merge profiles under these conditions. When attempting to merge an anonymous user to a known user profile, but that known user profile currently has an active session. When attempting to merge anonymous user B with known user X, but anonymous user A already merged with known user X in the last 30 minutes.

When Merging Occurs

When Merging Doesn’t Occur

When Personalization merges two or more user profiles, it stores all historic events, transactions, and interactions for those user profiles based on the following logic:

If an identity type exists for only one user profile, Personalization retains that identity type and adds it to the merged user profile.
If an identity type exists in more than one user profile, Personalization retains the identity type with the latest timestamp and adds it to the merged user profile.
If metadata doesn’t exist or doesn't have a timestamp, Personalization uses the system updated timestamp instead.

If there isn't shared identity type data between the user profiles, Personalization doesn’t forcefully merge them. For example, Personalization doesn’t perform a request to rename, or merge, LoyaltyID 123 to LoyaltyID 567 if there's no shared identity type data between the two user profiles.

Even when there’s a matching identity attribute, Personalization doesn’t merge profiles under these conditions.

When attempting to merge an anonymous user to a known user profile, but that known user profile currently has an active session.
When attempting to merge anonymous user B with known user X, but anonymous user A already merged with known user X in the last 30 minutes.