Prefilling Form CTAs is a feature that is automatically implemented with your Hub when integrated with Marketo.
When a user has filled out information on a Form CTA and later views another Form CTA integrated with Marketo, any data previously entered will be automatically filled into the form fields.
The way that Form CTAs are prefilled is through the use of cookie tracking. Once a user visits a Hub, they are assigned an ID within a cookie. Any data transferred to Marketo is tied to this cookie’s ID.
We use this ID when a user visits your Hub to retrieve their user profile. These cookies are created on the top level domain of the website on which they are created upon.
For Marketo, Hubs at http://hub1.company.com and http://company.com will both be able to share form field information since company.com is the top level domain.
This means that any existing known users in your Marketo database will have their Hub activity tracked when they engage in your Hub, even if they haven’t yet filled out a Form CTA. Wahoo!