Add All Records from a Source List to a Destination List

Add all of the records from a source list (specified by the sourceListId) to a destination list (specified by the listId). Records that are already members of the destination list will be ignored. The destination and source list IDs must be different. The destination and source lists must contain records of the same type (e.g. contacts, companies, etc.).

This endpoint only works for destination lists that have a processingType of MANUAL or SNAPSHOT. The source list can have any processingType.

This endpoint only supports a sourceListId for lists with less than 100,000 memberships.