How can I correlate an anonymous lead to a lead created by SalesForce?

[Anonymous]

I need to match up a lead created in SalesForce to its matching anonymous lead in Marketo for our channel attribution purposes. Does anyone know how to do this? I don't want to end up with dupes.

The flow is - the anonymous lead visits a landing page in Marketo. That landing page has an iframed form from our product that ends up creating a lead in SalesForce. Then our product sends them to a Marketo thank you page with their email address as a querystring parameter.

If I fake a form submit for just the email address it will create a lead in Marketo. Then I'll have two leads. I need the original information from the anonymous lead to do correct channel attribution on the lead that is being created in SalesForce.

We have avoided using the API because we used this in the past and if Marketo got backed up the API calls were just ignored.

[Josh_Hill13]

Sounds like a question for Sanford Whiteman​.

If they are Anonymous, then how would you associated the Anon record to a Lead in SFDC? You would have to match the Anon ID to the other Cookie. I suppose it's possible, however, it's not going to be perfect.

[SanfordWhiteman]

Thanks, Josh. Sharon, the usual workflow when you have a lead that's created on the SFDC side first is you ship the Munchkin cookie (_mkto_trk) along with the SFDC form post into a field on the lead (the field also being synced to Marketo, of course. Then, when the lead is synced over to Marketo, trigger a webhook to associate the lead with the cookie field.  This keeps the timing right.

[Anonymous]

Thanks so much. I'll talk to our product developers and see if they can support taking the Munchkin ID and passing it into SalesForce. I already have a field we stored the Munchkin ID in for another project.

Thanks!