Re: (DMARC) Why mailing lists are only sort of special

Dave Cridland <> Wed, 16 April 2014 20:01 UTC

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Date: Wed, 16 Apr 2014 21:01:04 +0100
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Subject: Re: (DMARC) Why mailing lists are only sort of special
From: Dave Cridland <>
To: "Murray S. Kucherawy" <>
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On 16 April 2014 19:41, Murray S. Kucherawy <> wrote:

> whitelist or a private one.  Are we certain, though, that it's flatly
> impossible to adjust lists in such a way that their traffic could be
> described by these mechanisms?
If you mean, can we change mailing lists such that they're describable by
DMARC without any change in behaviour, whilst maintaining the essential
premises of mailing lists, then I don't see a mechanism that would allow

If you mean, can we change DMARC (such that existing deployments will have
to change) such that a modified mailing list model (that handles the
existing use cases of mailing lists) would be describable, then I think
that's entirely possible.

Unfortunately, the only option I thought was possibly available isn't
permissible by the specification - therefore, the only solution involves
alterations to the deployed base, which has been ruled impossible for over
a year now.