Phishing continues to be a significant problem for hosting companies, mailbox providers, brand owners and, of course, for every internet user. This document iinforms all of these groups on the best current practices for reporting phishing URLs.

Although M3AAWG recommends blocking outbound port 25 traffic as the best option for controlling the flow of unwanted email traffic from an ISP’s customer space, such blocks may not always be possible, either for the short or long term. This document offers some alternatives for these ISPs by describing methods they can use to share their dynamic space information with others and allow remote sites to reject inbound mail traffic from dynamic address space.