SurfControl doubles the number of licenses for the SurfControl Web Filter so that computer IP and Username entries may be recorded.  Once all of the licenses are used up, it will place any new entries (users, IP Addresses) into an unmonitored list.  What I have noticed is that there were three types of entries: usernames, IP addresses, and computer DNS names.  I found that unmonitoring the IP Addresses would cause the username to stop recording if they were using the computer with that IP Address, and computer DNS entries did not appear to be required to log user activity. Some tips to help keep licenses under control are to set ex-employees and computer DNS entries to be "Unmonitored".  This will immediately free up another license while retaining the history of the unmanaged items.