What is Lashback?
Still have a question, spotted an error, or have a better explanation or a source we should cite?
Lashback UBL (Unsubscribe Blacklist) takes a unique approach - it specifically monitors for senders who fail to honor unsubscribe requests. By seeding unsubscribe probe addresses into email streams, Lashback catches senders who either don't process unsubscribes or continue mailing suppressed addresses.
Impact Level: Medium. Lashback is used by many email hygiene and compliance-focused organizations. A listing signals fundamental compliance problems that may trigger deeper investigation of your practices.
What triggers listing:
- Mailing to an address after an unsubscribe request was received
- Failing to process List-Unsubscribe header requests
- Using purchased lists that contain suppressed addresses
- Poor suppression list management across platforms
- Sending to recycled addresses that previously unsubscribed from other senders
How to check: Visit lashback.com/blacklist-lookup
Delisting process:
- Identify the specific address(es) that caused the listing
- Ensure your unsubscribe process actually works end-to-end
- Verify suppression list sync across all sending platforms
- Submit removal request demonstrating the issue is fixed
Before requesting removal:
- Test your unsubscribe links - do they actually work?
- Check processing time - are unsubscribes honored within 10 days (CAN-SPAM requirement)?
- Audit your suppression list management - is it centralized or fragmented?
- Review any purchased or third-party lists for suppression data
Lashback catches senders who break the most fundamental promise in email - that when someone says "stop," you stop. There's no technical complexity here, only the test of whether you respect your recipients' wishes.
Contributors
Who worked on this answer
Every name links to their profile. Every company links to their site. Real people, real accountability.
