Tracking Cookie in Email Link

[Jason_Scott]

When I send an email and the recipient clicks on a link, the link includes that recipient’s cookie, correct?  So, if the machine they are currently on has a cookie it should be updated/replace with the cookie from the email?  If they are on a device without a cookie it should now have their cookie?

Here’s common scenario.

New lead named Tom fills out Marketo form on their desktop. -> Tom now has Marketo ‘cookie’ on their desktop machine. -> We send an Email to Tom -> Tom opens and clicks on link from email on his iPhone -> The link Tom clicks on include his ‘cookie’ info in the URL -> The URL is a Marketo landing page with a form -> The form is set up to prefill however, it does not prefill even though his phone just added his cookie.

Are my links not adding the correct cookie?  Do the cookies in links not function in this manner?

[Anonymous]

Cookies are specific to each device and, within that device, specific to each browser.
That is defined by W3C.

The email's tracking link contains the Marketo token. The cookie itself is set by the landing page because emails do not contain JavaScript. 

The form fill out using iPhone will merge the anonymous lead with the existing one, based on email address.

[Jason_Scott]

What about multiple email address using the same device?

For example, I have contacts with both a business account and personal account.  How does Marketo 'know' which account the form is assigned to, business or personal?  I was under the impression the URL token would let marketo 'know' which email address it was from based on.  How does form prefill determine what information to use, URL token?

[Anonymous]

Breno, I was actually told the cookie was set by them clicking the email, but once I click on the email, the form is populating info from other leads. I change up emails a lot from testing, but it should still be able to pull the info of the lead who's actually clicking on their own email, right? Any thoughts or clear solution on this?