We have a standard DS button on cases for HIPAA verification and Related list to case which is Lookup to case from case contact (custom object). The issue is when configuring Recipient under relates list feature of DS I’m not able to limit the choice for sender to choose from case contact (a related list/lookup to case) Instead I’m getting all the org email ids to choose from which I don't want. I want users to send/choose from document to only related case contact object.