The InterServer DNS-based Blackhole List is a spam trap DNSBL. This list does not take spam reports from third-parties. All blocking is done based on email recieved to multiple spam trap email addresses.
After 5 days the ip is delisted. IPs which have been listed more than 4 times in a given month will be listed an additional 30 days.
Is the information on our site wrong or incomplete? You don't want us to monitor your blacklist? Or do you operate a similar blacklist? We would like to hear from you!
We keep some statistics on blacklists. Below is the graph for rbl.interserver.net. We test blacklists by asking them to respond to known IP's that are blacklisted and known IP's that can't be blacklisted. Not every blacklist has such IP's, we test them with what is possible. We keep if we get any response or error messages and the response duration. Lower response times are better. These statistics may be useful for email server administrators to pick which blacklist to use.