Yoav Nir wrote: > > On Apr 17, 2014, at 9:35 AM, Dave Cridland <dave@xxxxxxxxxxxx> wrote: >> >> Right now, my MUA treats this as a message >> "From John R Levine <johnl@xxxxxxxxx>". This means that any policy >> on the message origination comes from looking solely at the taugh.com >> domain. We'll pretend it has a DMARC policy. Herein lies the >> Yahoo/DMARC issue, because unless your policy essentially stipulates >> that the IETF is allowed to spoof you, we're stuck. > > Then perhaps this is what needs to change. John R Levine did not send > you a message. He sent a message to the list. It is the list software > that sent you a message. So perhaps the From field should have been > ?From: IETF Mailing list on behalf of John R Levine <ietf@xxxxxxxx>?. But that is EXACTLY what the IETF mailing list exploder *IS* doing exactly as it has been specified for ages: https://tools.ietf.org/html/rfc822#section-4.4.2 https://tools.ietf.org/html/rfc822#appendix-A.2 https://tools.ietf.org/html/rfc5322#section-3.6.2 The "From:" field specifies the author(s) of the message, that is, the mailbox(es) of the person(s) or system(s) responsible for the writing of the message. The "Sender:" field specifies the mailbox of the agent responsible for the actual transmission of the message. From: Yoav Nir <ynir.ietf@xxxxxxxxx> Subject: Re: (DMARC) Why mailing lists are only sort of special Errors-To: ietf-bounces@xxxxxxxx Sender: ietf <ietf-bounces@xxxxxxxx> Date: Thu, 17 Apr 2014 13:50:30 +0300 Message-ID: <B3467912-BDCA-4AE8-9939-60013DA99267@xxxxxxxxx> To: Dave Cridland <dave@xxxxxxxxxxxx> CC: "ietf@xxxxxxxx" <ietf@xxxxxxxx> Something as old as Outlook 2003 will properly display a message that is received with a "Sender:" as "<Sender> on behalf of <From>" -Martin