Abuse Report
An abuse report is when an email recipient forwards a complaint directly to abuse@marketo.com. Marketo’s Privacy and Compliance Team processes all complaints to these addresses and will unsubscribe the complainer when possible.
Feedback Loop Complaint
A feedback loop complaint is when an ISP forwards the complaints that originate from their users. For example, when someone clicks the SPAM or JUNK button in their email client.
ISPs that offer FBLs expect that subscribers like Marketo will mark the complainer as unsubscribed in the original database. Marketo does process FBL complaints and marks the email address as unsubscribed.
Additional Information:
Finding Leads that are Auto Unsubscribed for Email Spam Complaints / Feedback Loop (FBL)