Note: The following applies only to license files for versions prior to Veeam Backup & Replication 10.x. Starting with v10 all licenses contain no "Version=" string.
To check what version your license key is for, open the *.lic file in Notepad/Word and locate the section listed as "Version"
For example if your "Version" is listed as 9.x you are able to install any patch for Veeam Backup and Replication 9.0 or Veeam Backup and Replication 9.5
Starting with Veeam Backup & Replication v10 the license files are no longer version locked and are forward compatible.
Per the vee.am/supportpolicy: Please note that access to hotfixes, patches and updates requires active maintenance contract.