Importing Lists That May Contain Existing Leads/Contacts
My Marketo instance is set up to sync Leads and Contacts with Salesforce. The thing I'm trying to avoid is when a list is uploaded in Marketo and it contains someone that is already a Contact in Salesforce, Marketo will update fields like Name based on the data from the list. Sometimes this data is old, or bad, so I don't want it updating my Salesforce data. I've given the Marketo user profile in Salesforce the appropriate permisisons, but in order to update Contacts and Leads at all, they are given access to the Name field.
How do I prevent fields from being updated by new lists being uploaded in Marketo when they contain existing Contacts?