Chris Haynes wrote:
Are we still talking about using William's Record modifier
which says something to the effect 'my 2821 MAIL_FROM should
be from the same domain as (or identical to?) my 2822 FROM' ?
Yes, or the similar broken Sender-ID idea supported by Meng.
the presence of that modifier in the sender's SPF policy
constitutes the sender giving a carrier (MTA-operator) the
_authority_ to inspect at least that part of the message.
If it's there. Otherwise it's IMHO no legal problem beween
Sender and MDA, but maybe it's a legal problem between the
MDA operator and the final recipients. Especially if valid
mails "vanish" as in the "v=spf1 abused by PRA" scenarios.
Some users could sue their own providers after this stunt.
I'm ready to testify that this always was a criminal idea.
Bye, Frank