Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-21T08:38:33+00:00	DMARC	—	VALID	`a7a932f5b45a…`
2026-08-21T08:38:33+00:00	SPF	—	VALID	`cb3c730585bd…`