An options file can actually be used to deny all borrowing for concurrent licenses.
1. Please follow instructions in this article
https://support.tibco.com/s/article/Statistica-license-access-management-using-the-FLEXlm-Options-file, and make an option file with below content:
#all users cannot borrow
BORROW_LOWWATER APPS 9999
2. Save the option file in the FLEXlm folder and name it sta_flexlm.opt (.OPT extension)
3. Add options line in license file (stat.lic in FLEXlm folder), below the VENDOR line, and Save the license file:
OPTIONS=sta_flexlm.opt
4. Restart the Statistica License Manager service from Windows Control Panel > Services
5. The workstation users will get below message when they try to borrow the license:
"An error occurred during borrowing. No licenses to borrow"