I have to admit that I don't follow the "spam" world as closely as I used to, but I remember back around 2003, one of the hot topics was whether or not the various spam blacklists went too far
at times. The anti-spam fighters behind those lists would often take a rather... inclusive attitude to putting IP addresses and address ranges into their lists, and plenty of giant ISPs relied on the judgment of those spam fighters by simply plugging in their lists. This often resulted in significant collateral damage, as perfectly legitimate emails would get blocked as coming from a "spam IP." Of course, those lists needed to change frequently, but at times, they would just suddenly disappear
. That last link was about a popular anti-spam blacklist from Osirusoft that was shut down -- with its owners changing the settings to include all
addresses. The idea was to make it clear to ISPs who didn't pay attention, to stop using the list, but in the meantime, think of all the damage?
It looks like that same sort of thing may be happening six years later. Michael Scott
points us to the news of another long-abandoned blackhole list, called blackholes.us, that was abandoned a couple years ago -- but which some ISPs still rely on. However, whoever now controls the nameservers where blackholes.us used to be, apparently decided to set up a new "list" that (again) includes the entire range of IP addresses
-- so every query is returned as being a spammer IP.
Again, the idea is to force ISPs to stop using that blacklist -- and perhaps you can make the argument that (unlike the Osirusoft situation) these ISPs have had two years to stop relying on the "zombie" blacklist, but it still seems unwise to create so much collateral damage, just to force the issue.