How do you remove a contact from only 1 List via the API.
The process to remove a Contact from a List is to change the ContactLists portion of the Contact you want to update. You would simply remove the list in question from the Contact and then update the Contact with the changed List membership. For more information on how to do that, please see this documentation: http://community.constantcontact.com/t5/Documentation/Adding-a-Contact-to-a-List/ba-p/25121
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