How to detect fake bounces from spam filters?

Fake bounces may come from aggressive spam filters:

Detection signals:

Recent successful delivery: Address worked recently but now bounces. Unusual codes: Non-standard error messages. Mass bounces: Entire domain suddenly invalid. Inconsistency: Works from some senders, not others.

Why filters generate fake bounces:

Trying to get you to remove address. Obscuring spam filtering decisions. Legacy systems with odd behavior.

Verification approaches:

Cross-reference with engagement data. Check if domain is still operational. Compare across multiple sends. Manual verification for high-value addresses.

Response:

Do not immediately suppress. Apply longer threshold for suspicious patterns. Investigate before permanent action.

Not all bounces are honest. Some are filters trying to remove you from their inbox.