Licensing for the Total ZipCode Database is on a per copy basis as dictated by USPS licensing rules.
If the application that includes the USPS data is only deployed to a single location, only 1 license is required regardless of the number of users accessing the application. For example, if you install one copy of the application on your server, and 100 users point to the installation on the server, you only need one license.
If, on the other hand, the application that includes the USPS data is distributed to multiple locations (or installed on multiple computers), a license must be obtained for each location where the application is deployed. For example, if you install one copy of the application on 100 workstations you need 100 licenses.
FMS offers volume discount licenses for situations such as these.
For additional information on the License agreement, please visit: http://www.fmsinc.com/products/zipcode/licensing.html