With help from Return Path, Comcast has launched a complaint feedback loop.

feedback.comcast.com forwards mail reported as spam back to firms that mass-mail Comcast customers.

The loop also enables admins to receive copies of complaints that originate from their networks.

The system helps filter spammers that send objectionable material to many inboxes. And senders can view how many complaints, and what kind of complaints, result from their email messages.

Return Path covers more details about the liaison on its blog.