Posting this because I only found out this week and I suspect I am not alone. 𝗥𝗙𝗖 𝟵𝟵𝟴𝟵, Standards Track, published May 2026. The header line reads 𝗢𝗯𝘀𝗼𝗹𝗲𝘁𝗲𝘀: 𝟳𝟰𝟴𝟵, 𝟵𝟬𝟵𝟭. RFC 7489 is the document that essentially every DMARC guide, tutorial and vendor doc has cited since 2015. It has been historical for three months. 𝗪𝗵𝗮𝘁 𝗮𝗰𝘁𝘂𝗮𝗹𝗹𝘆 𝗰𝗵𝗮𝗻𝗴𝗲𝗱, 𝘄𝗵𝗶𝗰𝗵 𝗶𝘀 𝗹𝗲𝘀𝘀 𝘁𝗵𝗮𝗻 𝘆𝗼𝘂 𝘄𝗼𝘂𝗹𝗱 𝗲𝘅𝗽𝗲𝗰𝘁: Identifier alignment was section 3.1 in 7489. It is 𝘀𝗲𝗰𝘁𝗶𝗼𝗻 𝟯.𝟮.𝟭𝟬 in 9989. The definitions survived intact: relaxed alignment means the Author Domain shares an Organizational Domain with an authenticated identifier, strict means they are identical. So if your runbook or your internal wiki links to 7489 section 3.1, the section number is wrong and the concept is fine. That is the whole migration for most people. 𝗧𝗵𝗲 𝗽𝗮𝗿𝘁 𝘄𝗼𝗿𝘁𝗵 𝗿𝗲𝗿𝗲𝗮𝗱𝗶𝗻𝗴 𝗿𝗲𝗴𝗮𝗿𝗱𝗹𝗲𝘀𝘀: SPF can pass while DMARC fails, and this is not a bug or a misconfiguration. A forwarder that rewrites the return path makes SPF pass, but it passes for the forwarder's domain, which no longer shares an Organizational Domain with the From header. Alignment fails, so DMARC fails, on a message that authenticated perfectly. DKIM survives forwarding and SPF does not, because DKIM is a cryptographic property of the message while SPF is a property of the connecting IP. One caveat stated plainly: no RFC writes that in a single sentence. It is a derivation from the alignment definition plus RFC 7960 on interoperability. I would rather say that than pretend I found a quote. Links: RFC 9989 https://dub.sh/qIpjYgm RFC 7960 https://dub.sh/iioNfqn Has anyone here already migrated their internal documentation, or is everyone still pointing at 7489? https://dub.sh/zkBKfMr