ARC preserves authentication results across intermediaries such as mailing lists and forwarders. Each hop signs the results it saw, so the final receiver can trust an earlier pass even if SPF or DKIM broke in transit.
Do I need ARC as a sender?
No. ARC is implemented by intermediaries and receivers. Senders benefit indirectly when their mail is forwarded.
Which providers honor ARC?
Gmail, Microsoft, and Yahoo all evaluate ARC when deciding whether to override a DMARC failure.
Why does ARC (Authenticated Received Chain) matter for deliverability?
Forwarding and mailing lists are the largest source of legitimate DMARC failures. ARC lets receivers accept mail that would otherwise be quarantined under p=reject.
What is the first step to get started with ARC (Authenticated Received Chain)?
Check whether your inbound gateway or mailing-list software supports ARC sealing.
What is the most common ARC (Authenticated Received Chain) mistake?
Expecting ARC to fix your own outbound authentication; it only helps intermediaries.