After checking with the Support team looks like at the moment Marketo doesn't have any option to create a smart list that includes all the contacts of accounts that have no activity in SFDC.
It would be great to be able to run campaigns on contacts that belong to accounts for which my sales team has not registered any activity at all for any of the contacts.
At the moment, the only thing Marketo allows in this sense is to create a smart list with the filter 'Not activity was logged'. That filter will include every contact who doesn't have activity logged at the contact level. However it doesn't take into consideration if other contacts of the same account have had activity in SFDC.
So for example, I have this company: 'Company A' which has 2 contacts: Anna and Denisa. Denisa doesn't have any activity recorded in SFDC but Anna does has activity in SFDC. In my desired smart list, Denisa should not be included because even though she doesn't have any activity, there's another contact in that same account that does.
Hope this makes sense 🙂
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