DMARC Policy Changes

Fortune 100 DMARC reject coverage ticked up from 76 to 77 out of 100 domains (77%). Allstate was the sole mover, graduating from p=quarantine to p=reject and signaling the completion of a likely phased rollout.

76 → 77 of 100 at p=reject

The Tranco top-500 sector held flat at 215 out of 424 measured domains at p=reject (50.7%). While windowsupdate.com upgraded to p=reject, no net change was recorded, suggesting offsetting movement elsewhere in the sector.

215 → 215 of 424 at p=reject

Hospital systems posted the strongest sector gains this month, climbing from 18 to 20 out of 25 tracked domains at p=reject (80%). Both movers — Memorial Sloan Kettering and CommonSpirit Health — jumped directly from p=none to p=reject, bringing the sector close to full enforcement coverage.

18 → 20 of 25 at p=reject

The top-50 university sector added two more domains at p=reject this month, rising from 15 to 17 out of 50 tracked domains (34%). NYU and Indiana University both moved directly from monitoring-only (p=none) to full enforcement (p=reject), a notable leap that skips the quarantine intermediate step.

15 → 17 of 50 at p=reject