LashBack has introduced a UBL (Unsubscribe Black List) available for public use. The LashBack UBL lists the IPs of senders judged abusive for sending email to addresses harvested from suppression lists.

Putting your email address on a suppression list by indicating "unsubscribe me" or "don't email me" is supposed to insure that you do not get email from a particular sender or their affiliates. Yet some abusive senders use remove requests to build a list to send more unwanted mail to.

LashBack has been monitoring sender unsubscribe compliance since 2003. During this period, LashBack has compiled sender unsubscribe compliance failure in four primary categories:

1. Which senders fail to provide a working unsubscribe mechanism
2. Which senders do not honor unsubscribe requests within 10 business days
3. Which senders allow consumers unsubscribe request to be abused (i.e., shared with other parties to send more spam)
4. Which senders are taking suppression lists from other organizations and sending email to these lists

LashBack’s UBL only lists the IP addresses of senders who are using email addresses harvested from suppression lists (point 4). 

This free service is intended to provide all receivers and reputation providers a baseline of data to help block the sender’s with the worst reputations.  All IP addresses listed on in our service are being continually monitored and the list is updated hourly.

UBL Comparisons:
Percent also on SpamHaus:  34%
Percent also on SpamCop:  10%
Percent also on Sorbs:  8%
UNIQUE IP’s on UBL:  61%

The UBL database is provided free for both commercial and non-commercial use. Zone transfers, adhoc web queries, and DNSBL queries suitable for all mail servers are available immediately.

Details: www.LashBack.com/ubl.htm