Cannot apply the individual '.slf' license files into Symantec Installation Manager (SIM) from 8.1 version onwards as they will not override.
The individual 8.1 '.slf' license files are not summed.
From 8.1 version onwards, if there are multiple '.slf' license files received from Symantec, ensure that they are getting merged. If they are not getting merged, then kindly contact Symantec Technical Support.
After receiving the necessary SLF license files, follow below steps to install them.
Note: Please make sure that the multiple slf files what you receive from Symantec's Customer Care team should be of the same version.