"Smart Rules" for Progressive Profiling on Forms

We're trying to figure out a way to add a "Smart Rule"-type function to our Progressive Profiling fields on our forms. We have a bunch of leads that we generated via Unbounce that we exported and now want to upload to Marketo / SFDC, but many of those leads are lacking Company, First Name and Last Name values. We're planning on setting those 3 fields as [not provided] (if they're blank) in order to upload them to a SFDC Campaign (which is synced with a Marketo program) -- and SFDC Campaigns require a value for last name and company. However, if/when these leads return to another one of our landing pages in the future, we want to re-serve the Progressive Profiling questions of First Name, Last Name and Company so that we can eventually gather accurate information for these fields and replace the [not provided]. Is there a way that we can set a "Smart Rule" that, for instance, says: "if First Name = [not provided], serve the First Name field on the form"?

Thanks in advance!