On Sun, Aug 5, 2018 at 5:46 PM, Rich Kulawiec <rsk@gsp.org> wrote:
This is a solvable problem. If they're sending unsolicited bulk email (aka "spam"), then they are, by definition, spammers. Block them and move on. If/when they decide to send proper DMCA notices and send them to the proper address, perhaps you can then allow them to petition for the privilege of access to your mail system.
---rsk
But then the question becomes "how are they supposed to find the 'proper address' for their reports?" If you run a whois server and link it from your RIRs or create a custom "DMCA Compliance" POC in the RIR listings then you could maybe list that sort of thing there, but most address maintainers do neither, so by default whatever address is listed on those net block records with the RIR seems appropriate enough to me. There's no other established protocol for determining an appropriate contact (like calling the associated phone number and asking, or trying to determine your web url and browing that site for it, or something else much more involved.) If there should be a different protocol established for that, then we need to figure it out and document that and get a critical mass of reporters to buy in to it.