On Thursday, March 10, 2005, 11:34:32 PM, Jeff Chan wrote:
However of those 94, 92 appear to not resolve any NS records which means they're either not registered, had their registrations expire, revoked, etc. So they're not too useful for spammers. They could appear in spams, but any web sites referenced by them would not resolve.
I should add that if a domain doesn't resolve it can still appear in spams, for example due to error or the spammer not noticing that the domain had been cancelled, etc. However most spammers keep pretty careful track of which domains are currently active. It doesn't benefit them too much to advertise a domain which doesn't work, so that tends not to happen too often.
It's also possible that these 92 did work before and perhaps appeared in some older spams. Spam is fairly dynamic so it can be useful to work with fresher examples. There appears to be a recency effect where new domains appear in spams and older ones are abandoned.
Jeff C. -- "If it appears in hams, then don't list it."