RFC 8058 is an internet standard that defines ARC (Authenticated Received Chain), a mechanism designed to preserve email authentication results when an email is forwarded.
In simple terms, RFC 8058 helps prevent legitimate emails from being marked as spam when they pass through mailing lists, forwarding services, or security gateways.
Email authentication methods like SPF, DKIM, and DMARC work very well when an email goes directly from sender to recipient.
However, problems arise when emails are forwarded. Forwarding can:
RFC 8058 was created to solve this problem by allowing each server that handles the message to record and cryptographically sign the authentication results.
ARC is the system defined by RFC 8058. It creates a chain of trust as an email travels across multiple servers.
Each server that supports ARC:
The final receiving server can then decide whether to trust earlier authentication results, even if the message fails checks later due to forwarding.
This allows legitimate forwarded emails to reach the inbox instead of being rejected or sent to spam.
RFC 8058 defines three main ARC headers:
ARC is particularly important in scenarios such as:
By preserving authentication results, RFC 8058 plays an important role in improving email deliverability.
While ARC does not replace SPF, DKIM, or DMARC, it complements them and helps mailbox providers make more informed filtering decisions.
No. RFC 8058 does not replace DMARC.
Instead:
Together, they improve trust and reduce false positives in spam filtering.
Mailpro supports modern email authentication best practices and works seamlessly with:
Using proper authentication and deliverability tools helps ensure your emails remain trusted—even when forwarded.
Why RFC 8058 Exists
What Is ARC (Authenticated Received Chain)?
How RFC 8058 Works (Simplified)
ARC Headers Defined in RFC 8058
When Is RFC 8058 Especially Useful?
RFC 8058 and Email Deliverability
Does RFC 8058 Replace DMARC?
RFC 8058 and Mailpro
Related Glossary Terms
Mailpro and RFC 8058
One-click unsubscribe, added automatically
Mailpro injects the List-Unsubscribe and List-Unsubscribe-Post headers RFC 8058 requires — the Gmail and Yahoo 2024 bulk-sender mandate is met on every campaign without you setting it up.