Worst of the Worst

Rick Castello
Product Manager

Today we are proud to release the latest version of the Return Path Reputation Network Blacklist. Internet service providers use our blacklist to make blocking and filtering decisions about the email entering their network. Now those choices will be even easier to make and more accurate than ever.

The Reputation Network Blacklist is a real-time list of senders categorized as the “worst of the worst” based on the data we receive from mail administrators and ISPs into our Reputation Network, a collaborative data cooperative of ISPs and reputation data providers. The Return Path Reputation Network calculates the likelihood that emails from any email server may be objectionable or otherwise unwanted based on measurement of past performance. This is not a value judgment about the content of the message, but is based on whether past messages from that server were considered to be “spam” by recipients (along with other metrics.)

The new version of the blacklist is vastly superior to the 1.0 version based on size, methodology, updates, and scoring. It is updated in near real-time, for fast response to changing data – and we now have more data sources than ever before, allowing for wider and deeper coverage of IPs.

The blacklist is compiled using a predictive behavioral model that analyzes more than 600 variables for each sending IP address. This model is unique because it scores IPs in near real time and incorporates volume, spam traps, and complaint sources. This comprehensive methodology based on a wealth of source reputation data, and rapid zone updates offers the most current and accurate sender reputation profiles available.

If you are an ISP who would like to learn more about the RNBL and how to use it in your mail systems, visit the RNBL page or contact us today. Senders – Are you concerned that you may be on the blacklist? Go the senderscore.org blacklist look-up page to do a real time check to determine if a particular email server is listed on the blacklist.

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