What is Backscatterer?

Backscatterer (ips.backscatterer.org) specifically targets IPs that generate backscatter - bounce messages sent to forged sender addresses. When spammers forge your address as the sender, and receiving servers bounce those messages back to you, the bouncing server creates backscatter.

Impact Level: Low. Backscatterer is a specialized list addressing a specific abuse pattern rather than general spam.

Zone: ips.backscatterer.org

What triggers listing:

• Sending bounce messages (NDRs) to addresses that didn't send the original message
• Mail servers that don't reject spam at **SMTP** time (accept-then-bounce pattern)
• Misconfigured auto-responders replying to forged addresses

Why this matters:

• Backscatter is itself a form of spam - innocent parties receive unwanted bounces
• Properly configured servers reject spam during **SMTP** transaction, not after
• Accept-then-bounce patterns waste resources and harm innocent domains

Delisting: Fix your mail server configuration to reject spam at **SMTP** time rather than accepting and bouncing. Then request removal.

How to check: backscatterer.org

Backscatterer catches servers that shoot first and ask questions later - accepting mail they'll just bounce anyway, creating collateral damage for everyone whose address was forged.