Double-Optin Process through API form external preference center

[Hans-Martin_Pfa]

Hi, does anyone can share experiance and best practice on how to setup the double-optin process with Marketo using the API.
We are working with our own preference-center, customer submit a subscription-from from our preference-center, how to run this through
Marketo, to send the opt-in email - and keep the lead-record(person) in a status "waiting for optin" until a contact has confirmed.

[Josh_Hill13]

Right...what about the API is unclear? What is the process chart for what you want to do?

Building a Full Subscription Center in Marketo - Marketing Rockstar Guides

[SanfordWhiteman]

The thread should be moved to Products​ (Move link is at the right).

I hope you mean Forms JS API, not REST API, because the latter is a no-go for forms.