Not a lot here, not a lot of info to find for obvious reasons
Volume licensing
licensingdiag.exe
LicensingUI.exe
slmgr.vbs
slui.exe
changepk.exe
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SoftwareProtectionPlatform\Activation
sppwinob.dll
%SYSTEMROOT%\System32\spp
The sppsvc service.
Windows product key
Possible license states are: