I'm wondering if a lead's campaign membership is purged in SFDC (just cleaning out very old campaign memberships), will Marketo see this and re-populate the campaign members?
The answer to your question is no. When a lead is removed from a campaign or deleted in Salesforce, that information is recorded in Marketo, and the lead record will not be put back in the campaign.
to piggyback on this question, if people in that list had unsubscribed to email, would they still be in the unsub list or with them being removed would that also take them off of that lits?
If a lead is unsubscribed at the time they are deleted, Marketo will remember that email address. Any leads created in your instance in the future with the same email address will be created with Unsubscribed set to True. This is what's called the Durable Unsubscribe feature.
Thanks for clearing this up. I was thinking that would be deleted everywhere and from all lists.
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