What role do feedback loops play for cold domains?

Feedback loops (FBLs) are services where mailbox providers report when recipients mark your messages as spam. They're valuable early warning systems for cold email senders.

How FBLs work:

You register your sending IPs or domains with providers that offer FBLs

When a recipient clicks the spam button, you receive a report

Reports identify the complaining address (usually) and the message

Major FBL programs:

Microsoft SNDS and JMRP for Outlook/Hotmail

Yahoo CFL (Complaint Feedback Loop)

Gmail doesn't offer traditional FBLs but provides data through Postmaster Tools

Value for cold email:

Identify which messages trigger complaints

Remove complainers immediately to prevent further damage

Detect targeting problems (certain segments generating high complaints)

Early warning before reputation damage becomes severe

Important note: FBLs require registration and sometimes minimum volume thresholds. Set them up before problems occur, not after.