Definition
A feedback loop (FBL) is a service offered by major ISPs that sends reports to senders whenever a recipient marks their email as spam. The reports include the email address of the complainant and the timestamp, enabling automatic suppression of future sends.
Setup Process
- Register for each ISP's FBL program (Google Postmaster Tools, Yahoo FBL, Outlook SNDS)
- Configure a dedicated FBL processing address (typically abuse@yourdomain.com)
- Set your Return-Path to route bounces and FBL reports to this address
- Automate processing: parse incoming FBL reports, extract complained addresses, add to suppression list
- Monitor complaint volume and address any campaigns triggering excessive complaints
Why It Matters
ISPs expect senders to honour FBL data. Failure to suppress known complainers results in escalating spam filtering. Most ISPs require FBL processing as a condition of maintaining good sending reputation.
Related Glossary Terms
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