changes

Email feedback loops have a long history as a component of the sending, receiving and handling of email messages en masse. I vaguely recall that AOL was the first entity to set up what we commonly think of as a feedback loop — with their now-common process to register your sending IP addresses with the ISP, and if anybody complains about your mail, the ISP will send you a report back with the full headers and source (with perhaps a bit of it redacted at the instruction of some lawyer) so that you can count, report on, and review these spam reports. Review of that data could identify bad senders, identify bad lists, and help stop mail to people who don’t want the mail. (Indeed, the Wayback Machine shows mention of AOL’s Feedback Loop all the way back in 2004.)As that feedback loop mechanism grew in popularity, various other ISPs