> What would be the benefit of setting up DMARC on top?
Some mail providers will junk your mail if you don't have a reject/quarantine DMARC policy because you're seen as enabling the spammers so everything out of your domain must be punished.
Some mail providers will junk your mail if you don't have a reject/quarantine DMARC policy because you're seen as enabling the spammers so everything out of your domain must be punished.
> Requirement: Must exist (minimum p=none)
This doesn't support ggp's claim.