This is not precisely true. You could force this through some methods. Yes, Visits page anon activity will merge to the Known record if the Munchkin ID assigned matched, that is, they filled out a form and were properly associated. Marketo does NOT push this history to SFDC Marketo DOES push this data to SFDC within Marketo Sales Insight. Which is precisely what you want. The data itself doesn't reside in SFDC though. It's just a window into Marketo. If you did want to record this detail in SFDC, you could push Tasks to SFDC, but this is sync intensive and takes up data. You could also go to Admin > Salesforce and ask it to sync several of those Activities, however, it won't push the Visits before they were Known.
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