/history The history of email sender guidelines https://www.hirano.cc/no-auth-no-entry/
Sender guidelines enforcement (Bulk sender case)
1. What is the timeline for enforcement of sender guidelines?
2024-03-08
Starting in April 2024, we’ll begin rejecting non-compliant traffic.
Rejection will be gradual and will impact non-compliant traffic only.
We strongly recommend senders use the temporary failure enforcement period to make any changes required to become compliant.
Enforcement for these requirements will begin no earlier than June 2024:
DMARC record with a minimum policy of none (p=none). Learn more about DMARC record values.
One-click unsubscribe in marketing messages
Mitigations unavailable when user-reported spam rates exceed 0.3% or
if the sender has not met the authentication or one-click unsubscribe requirements.