RFC 8601 - SMTPedia

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RFC 8601

Headers & MIME

The Authentication-Results Header: Parsing SPF, DKIM, DMARC and ARC Verdicts (RFC 8601)

Alaa 27 August 2026

The Authentication-Results header (RFC 8601) records SPF, DKIM, DMARC, and ARC verdicts per message at the receiver. Covers the exact format with authserv-id and ptype fields (smtp.mailfrom, ...

RFCs

RFC 8601: Message Header Field for Indicating Message Authentication Status

Alaa 22 July 2026

Defines the Authentication-Results header that records SPF, DKIM, and DMARC check outcomes for downstream processing and BIMI.