The Composite Blocking List (CBL) is a free list meant to block "IPs exhibiting characteristics which are specific to open proxies of various sorts." It should block very little non-spam.

It is incorporated into Spamhaus ZEN. If you are already using Spamhaus ZEN, you do not need to utilize the CBL separately. (Spamhaus ZEN is highly recommended.)

Here's a link to the DNSBL.com review of the Composite Blocking List (CBL).

View the Data Interpretation Guide for a quick overview of how this data is compiled. For a more detailed understanding of what constitutes spam and ham (non-spam), this page provides further insight.

For more information on blacklists, vist DNSBL Resource Stats Center or Main Website.

This page was last updated: Sun Jun 15 13:43:33 PDT 2008.