I uploaded a list and the SFDC type (lead, contact, etc), populates for some but not others. Any clue why this is happening? Thanks.
You cannot import new leads into Marketo and assign them as contacts in SFDC, Marketo only sees people (leads and contacts). After importing into Marketo, you can then convert them on the SFDC side in order to assign to the correct account.
Yes, I should have clarified, the SFDC for newly uploaded leads are null. Why is that?
They will not have an SFDC type until they are synced to SFDC.