ATT / Bellsouth Email Feedback Loop

Bob Poortinga bobp+nanog at
Thu Feb 25 19:33:45 UTC 2010

Wade Peacock <wade.peacock at> writes:
> We have found ATT to be heavy handed with their email (spam) filtering. 
> Without warn all of our mail servers will be denied from delivering email 
> to their many domains (,, etc). They have a removal 
> request form (like most other large ISPs) which takes 2 days to process. We 
> never find out why the we get listed.

We have dealt with issue in the past.  AT&T maintains an internal
blacklist and their blacklist policies are not published.  There is
also no feedback loop mechanism in place, AFAICT.  I do know that
sending backscatter to AT&T will get you in their blacklist.  If your
server sends NDRs instead for rejecting during the SMTP transaction
for 5xx type messages then that is probably what got you on their list.

The email address we have used at AT&T to resolve these issues is:
<abuse_rbl at>.  Make sure that all of issues which caused
your blacklisting are resolved because if they put you on the list again,
it is much tougher to get removed.

Bob Poortinga  K9SQL        <>
Bloomington, Indiana  US

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