When merging person/lead records within Marketo with the Merge function, what happens to the SFDC records, do they sync up with the merge function performed in Marketo?
Yes, unless you are missing permissions.
See here: Understanding Merges in Marketo
and here: The Results in Marketo of Merging Leads or Contacts in SFDC
So you will want to test to make sure.
It's not just a question of permissions. Some merges in SFDC are simply not possible, such as merging 2 contacts that do not belong to the same account. Lead to contact merge through conversion might also be problematic, depending on how the convert process is customized in your SFDC instance. Best case, the merge will fail in SFDC and this will prevent the merge to occur in Marketo. Worst case, the merge will occur, but the result will be wrong data.
So, be careful
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