Interceptor for Non-Subscribed Bulk Electronic Messages

Abstract

Bulk mail subscriptions by including a bulk mail class indicator and a sender identifier key value in the header portion of an electronic message. Messages which are properly identified as bulk class and include an approved sender identifier value are passed directly to the intended recipient. Messages which are properly identified as bulk class but which do not contain an approved sender identifier value are rejected or intercepted. Messages which do no indicate themselves to be bulk class, but which are determined to have characteristics of bulk mail are rejected or intercepted, as well.

1 . A system for intercepting unwanted electronic bulk mail messages comprising:
 an inbound message examiner configured to:
 examine a header portion of an electronic message destined to an intended recipient to find a bulk class indicator; and 
 responsive to finding said bulk class indicator, further examine said header portion to find an approved sender identifier value; 
   a message passer configured to, responsive to finding both a bulk class message indicator and an approved sender identifier value, forward said message to said intended recipient, including said header portion with said bulk class indicator;   a bulk analyzer configured to, responsive to finding no indication of said bulk class indicator, analyze said message for bulk message characteristics comprising analysis selected from the group of detecting a number of recipients contained in the message recipient list exceeding a pre-determined limit, detecting previously determined objectionable strings or words in the message, detecting instructions in the message regarding how to unsubscribe, detecting text within the message which is similar to message content contained in other messages addressed to recipients other than said intended recipient, and detecting a plurality of messages sent within a pre-determined period of time from a same sender; and   a message interceptor configured to, responsive to finding a bulk class indicator but not finding an approved sender identifier, or responsive to determining that the message has bulk message characteristics, intercept the message the message by blocking forwarding of the message to said intended recipient.   
     
     
         2 . The system as set forth in  claim 1  wherein said header portion of a message comprises a Simple Mail Transfer Protocol message header portion. 
     
     
         3 . The system as set forth in  claim 1  wherein said message passer is further configured to check a whitelist for entry of said intended recipient. 
     
     
         4 . The system as set forth in  claim 1  wherein said message interceptor is further configured to delete an intercepted message. 
     
     
         5 . The system as set forth in  claim 1  wherein said message interceptor is further configured to store an intercepted message in a low priority folder.