List of email feedback loops

As of 2016 these are the location of feedback loops that mail service owners can use to get alerts about abuse originating from their networks.

AOL - AOL Postmaster - Feedback Loop Request

Comcast - Comcast.net Feedback Loop - Feedback Loop Request Form

EarthLink - Collection of Best Practices for Email Senders on the EarthLink Network

FastMail - FastMail Feedback Loop Request Form

Gmail - Gmail Spam FBL Enrollment Form for ESPs

Hotmail / Outlook.com - Sign in to your Microsoft account

Synacor - Synacor - Feedback Loop Request Form

Time Warner - Time Warner Cable - Feedback Loop Request Form

Yahoo - Postmaster | SLN3438 - Complaint Feedback Loop program (Yahoo Complaint Feedback Loop (CFL))

Zoho - http://fbl.zoho.com/

If anyone wants to quickly sign up for all the different feedback loops, you can use this free service: Email Feedback Loop Submission Service

Here are a few additional ones.

Excite/Bluetie - BlueTie Feedback Loop - Feedback Loop Request Form

Cox - Cox - Feedback Loop Request Form

Rackspace - Feedback Loop Request Form - Rackspace

Tucows/OpenSRS - OpenSRS - Feedback Loop Request Form

Terra - Terra - Formulário de Pedido de Feedback Loop

United Online - http://www.unitedonline.net/postmaster/whitelisted.html

Usa.net - Feedback Loop Request Form - USA.net