I would like to track the "forward" rate of an email and see who forwards and received the forward emails. I read that you may add a "Forward to Friend" link ('Forward to a Friend Link' in Emails - Marketo Docs - Product Docs ). And if one uses the "Forward" button in email clients, the email will still be logged in as the one who forwards the email even if the email is opened by the one who received the forwarded email. In reality, we can't control which way people use to forward emails. Does that mean there are no way to get a total number of forwarded emails?
That's right, it is not technically possible. Only the "Forward to a Friend" button within the email can allow us to understand that there is a new recipient of the message. If a lead forwards an email to someone via their email client's forward button, this action is unknown to Marketo and we cannot differentiate activities taken on the forwarded mail from the original.
If people use the "forward" function on their email client, no, there is no way you can track this.
We could imagine a pixel tracker that would count how many times it has been downloaded in a different laptop, but if people do not download images, it would not work anyway.