Re: [dmarc-ietf] Spirit of RFC8601 section 5 for invalid A-R headers

Damian Lukowski <> Fri, 03 April 2020 20:53 UTC

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From: Damian Lukowski <>
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Date: Fri, 3 Apr 2020 22:53:57 +0200
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Subject: Re: [dmarc-ietf] Spirit of RFC8601 section 5 for invalid A-R headers
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> Honestly, it doesn't matter.  The only A-R headers you can trust are
> the ones that your own system added, and the point of that text is
> that you should delete ones that look like yours but that you didn't
> add.

How can a MUST not matter? My personal interest in this area is what
needs to be done according to the specification, which unfortunately
uses a metaphoric verb for the condition of the MUST.