[Mailman-Users] Excessive bounces to list members on my list

[Robert Heller]

At Tue, 29 Apr 2014 16:32:18 -0700 Mark Sapiro <mark at msapiro.net> wrote:

> 
> On 04/29/2014 01:25 PM, Joseph Brennan wrote:
> > 
> > I think Gmail is doing the same.  It's a touch evil to make mail from
> > aol and yahoo less deliverable than your own... but it's what they asked
> > for.
> 
> 
> Gmail is honoring DMARC p=reject, but they have some magic for not
> applying it to mail from some lists. How they recognize list mail is
> probably a trade secret.

Actually probably not.  I think the giveaway is the presense of the various 
list specific headers (X-Mailman-Version:, List-Id:, List-Unsubscribe:, 
List-Archive:, List-Post:, List-Help:, and List-Subscribe:).  In other words, 
they are using a *smart* filtering program, and not some dumb clueless test.

> 
> They are also rewriting From: headers in outgoing googlegroups posts
> whose original From: address is in a domain with DMARC p=reject.
> 

-- 
Robert Heller             -- 978-544-6933 / heller at deepsoft.com
Deepwoods Software        -- http://www.deepsoft.com/
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