The latest version is 11.7 of the FlexNet (FLEXlm) executables lmgrd.exe, lmutil.exe, lmtools.exe and lmadmin.
COMPATIBILITY: The version of the license server manager must be greater than or equal to the version of FlexNet Publisher used in the application/application's vendor daemon (for Autodesk it is adskflex.exe). You can always use the latest license server manager and utilities; they will be backward-compatible with your application and its license file.
Download them here and select your Operating System. Normally updating is not needed unless your application vendor requires it. But if you experience problems in some way, then it can be a good idea to see if it helps with the latest version.
To upgrade. Take backup of the old exe files. Stop the license service(s). Replace the exe files. Start the license service(s). This can in most cases be done even during daytime and the users will not notice anything but it is usually best to wait until there are few users having licenses in use.
For license usage reports of FLEX enabled software and other software both network licensed and single licensed use JTB FlexReport.