DMARCbis Is Now RFC 9989: What Actually Changed, and the t= Trap Everyone Is Getting Wrong
DMARCbis stopped being a draft in May 2026: it is now RFC 9989 (core), 9990 (aggregate reporting) and 9991 (failure reporting), and it obsoletes the original RFC 7489 that almost every DMARC guide still cites. The record you publish keeps working, but three things changed under the hood - the Public Suffix List is replaced by a DNS tree walk, pct/rf/ri are removed, and a new np= tag is the sharpest anti-spoofing control in the record. Watch out for t=: it steps your policy down one level, it does not disable it, and secondary sources are already calling it pct=0 by mistake.
EffectivePublished May 2026