How can regional providers enforce stricter DMARC policies?

Regional providers can enforce stricter DMARC policies than global providers, particularly those serving privacy or security conscious markets. Some regional ISPs reject messages failing DMARC entirely, even when the sender's policy only requests quarantine.

This stricter enforcement reflects different risk tolerances. A regional provider serving a security focused user base may prioritize protection over deliverability, choosing to reject suspicious mail rather than risk spoofing attacks reaching users.

For senders, this means DMARC configuration matters more at certain regional providers. Test delivery to regional domains before tightening your DMARC policy. What works at Gmail might cause rejections at regional providers with stricter interpretations of authentication signals.