On 2 March 2018 at 21:45, John Johnstone
> It seems somebody gave some fairly purposeful thought into coming up with
> the algorithms to generate these. I'm curious to know what peoples thinking
> is as to the hat color of these attempts. Particularly if there are any
> opinions on the risk / need to block them.
Tools like hunter.io try to suggest you the "pattern" used by a
company so that you can guess email address for named people, but they
mainly use crawled data, so I think your suspect is findanyemail.net:
put a name and surname and your domain and it will try to guess the
patterns and "verify" them.
That said, about the hat color....
We're a small ESP and I think email validators/cleaners are making OUR
We can identify bad clients/customers as soon as they load their list
if it contains very old expired domains, spamtraps, fake domains,
emails like "e...@ail.jpg" or some .pdf TLD. Or we can identify "non
confirmed" lists because of the presence of many typos domains. This
let us block and vet the senders BEFORE they abuse our tool (and send
But if they come with a cleaned list then it is harder for us and we
have to do the first send in order to understand they are spammer, and
sometimes when they have mostly b2b addresses it is hard because of
missing FBLs from the providers and very low feedback from recipients
that know it is spam.
I think that from a receiving MTA point of view, this is the same: if
they hit your spamtraps (or simply invalid recipients) you have more
chance to deal with them "correctly" and early.
So, from our point of view, bulk list validators are bad and I can't
see a valid point to use them, but trying to trick the game (for short
term spamming results).
That said, some ESP have a different opinion from me, as I just read
this recent post:
I'm interested in how receivers see this email verification tools and
how many of them deployed protections from them (e.g: identify their
IPs and refuse or fake the answers to their requests or anything
PS: between the many email verification tools, Kickbox
(https://kickbox.com/about) have a claim "Kickbox is a white hat
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