After someone receives a confirmation email, we'll be asking them to click on a link to go to a landing page on our website. We want to embed a very simple Marketo form - two fields max. Neither of those fields are ones to identify someone (e.g., email address). When a known visitor clicks submit, will the values populate their existing lead record in Marketo?
I believe so -- assuming tracking is enabled in the confirmation email link, that should be enough to associate the form submission with their existing record.
Let us know what you find out! I'd be concerned it would make a new lead every time, but it may use the munchkin cookie as a unique identifier in place of an email address.
Will do, Grant. We're about to test it.
You never need the Email field if you have an associated cookie. That's how Known Lead HTML functions: there is no Email field in the KL HTML form post.
Note having an empty Email is different and bad.