Re: [dmarc-ietf] ARC questions

Dave Crocker <> Mon, 23 November 2020 22:52 UTC

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To: John R Levine <>,
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From: Dave Crocker <>
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Date: Mon, 23 Nov 2020 14:51:59 -0800
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Subject: Re: [dmarc-ietf] ARC questions
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On 11/23/2020 2:42 PM, John R Levine wrote:
>> Forgive me but I believe misbehavior by mailing lists has never been 
>> meaningfully documented for this work.  Quite the contrary.
> I believe that Brandon has specifically said that Gmail sees this 
> problem and that is why whitelisting mail from mailing lists isn't 
> adequate. 

And that constitute "meaningfully document[ing]"?

My point wasn't that it isn't a valid concern, but that it was not 
explicitly stated as the motivation. Again:

> ARC deals with the problem that most list software forwards everything
> with a subscriber's address on the From: line and does a lousy job of
> spam filtering. 
offers a characterization of mailing lists that hasn't been documented.

And, again, when ARC work was pursued, I don't recall anyone claiming 
that mailing lists were (significant) sources of misbehavior.


Dave Crocker

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