Using UTMs to Append Lead Source & Most Recent Lead Source
As a new Marketo user, I have a question about how to use UTM to append my first touch (lead source) and most recent lead source field. I want to set my Marketo fields so that based on the UTM (or a default 'direct traffic' if there's no UTM), it would append the information into the Lead Source field and then lock the value in that field so that it cannot be updated. However, at the same time, I have a custom field called Most Recent Lead Source that is constantly being overwritten so that every time a prospect comes across a link (with or without UTM), it overwrites the information on my Most Recent Lead Source field.
Does any have suggestions or experience on how they set up "multi-touch" within Marketo? Also, we do not use Marketo Landing Pages or Forms since we made the decision to use Wordpress.