Office of Technology Transfer – University of Michigan

A Mechanism for Making Communications Markets with Application to the Spam Problem

Technology #2768

Questions about this technology? Ask a Technology Manager

Download Printable PDF

Marshall W. Van Alstyne
Managed By
Drew Bennett
Associate Director - Software Licensing 734-615-4004


Due to its low cost, speed, and freedom from geographical constraints, email has become a ubiquitous and arguably essential means of communication. Unfortunately, the same properties that make it so useful, combined with its openness and trusting design, enable unscrupulous marketers to broadcast email to untargeted audiences. The result is unnecessary and unwarranted costs for recipients. Recent estimates indicate more than 50% of email is now spam, the volume of spam is growing rapidly, and worldwide costs exceed $20 billion annually. This enormous quantity of unwanted communications has reduced the signal to noise ratio of email to such an extent that it has become an issue of national importance.


University of Michigan researchers have created an economic-based solution to for regulating electronic messages; i.e. spam. Analogous to a standard bond mechanism, delivering email to an inbox requires an unknown sender to place a small pledge into escrow with a third party. If the recipient expects further communication with a particular sender, they can add the sender to a list of approved senders, which will allow the sender’s messages to be delivered to the recipient. An innovative method for managing this list of approved senders as well as a technique for soliciting electronic messages using the underlying principles of the bond mechanism are described in the present invention.

Applications and Advantages


  • Email filtering
  • Voicemail filtering


  • Limits the amount of unwanted email or voicemail