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Complaint feedback loops examples: what good and bad look like

Short answer

A good complaint feedback loops implementation follows these steps: Register your sending IPs and domains with each provider's FBL; Route FBL messages to an automated parser. A bad one typically registering but never processing the reports.

Feedback loops (FBLs) are programs run by mailbox providers (Microsoft JMRP, Yahoo CFL, Comcast, and others) that send you a copy or notice whenever a recipient marks your message as spam.

What good looks like#

  • Done: Register your sending IPs and domains with each provider's FBL.
  • Done: Route FBL messages to an automated parser.
  • Done: Suppress every complainer from all future marketing.
  • Done: Report complaint rate per campaign and per acquisition source.

What bad looks like#

  • Seen in audits: Registering but never processing the reports.
  • Seen in audits: Gmail has no traditional FBL; use Postmaster Tools spam rate instead.

How to move from bad to good#

Work through the good list in order and re-verify after each change. Most teams find one or two items from the bad list already present; fixing those usually produces the largest improvement.

Frequently asked questions#

Does Gmail offer a feedback loop?

Only an aggregate one via Postmaster Tools using the Feedback-ID header. Gmail does not return individual complaints.

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