On Sun, 12 Mar 2017 11:11:41 -0400, "Chuck Church" said:
Maybe a silly idea, but shouldn't the sale of a block of addresses (RIR ownership change) trigger a removal of that block from all reputation list databases? If I buy a car from a police auction, I'm fairly sure the FBI doesn't start tailing me, because the car was once used for less than legal purposes. New owner, clean slate.
How does Spamhaus find out the block has been resold? How do other DNS-based blacklist operators find out? How do all the AS's that have their own internal blacklists find out that they should fix their old listings? (Note that this is the exact same problem as "We got blacklisted because of a bad customer, we axed the customer, but we're still blacklisted", which has been a an unsolved problem for decades now). And it's awfully easy to game the system by just reselling the block between a group of shell companies run by bad actors.