OIT uses an email filtering technology to process incoming email for spam and viruses for the CU Boulder campus. This system scans incoming messages using an extensive collection of rules to determine the likelihood of each message being spam, then assigns a numeric score to each message.
Messages are given an "SBRS" (SenderBase Reputation) score and an IronPort SPAM Score. For SBRS, the range is from 10 (likely a trustworthy sender) to -10 (apparent spammer). A score of "none" indicates that there was no information about the sender at the time the message was being processed.
For the IronPort SPAM score, the range is 0-100. Email scored between 0-49 are considered "clean" and are delivered without alteration. Messages scored between 50-90 are considered "suspect" and are tagged with POTENTIAL-SPAM in the subject line. Messages with a score of above 90 are considered positive SPAM and are not delivered.
Note: SenderBase Reputation scores (SBRS) and the IronPort SPAM scores don't display in message headers.
You can configure your email client's filter to move potential spam to another folder where you can periodically check for false positives and delete the rest.
That way, you decide when to deal with spam, rather than having it interfere with reading your legitimate email.