There is a one-time fee of $300.00 for an OPC-UA license. cMT-SVR-200/cMT-SVR-202 are the only HMI products that require this one-time purchase.
Current cMT3000 series, cMT-G01/cMT-G02, and cMT-SVRX units have built-in OPC UA Client and Server functionality, no additional license needed.
cMT2000 series has only OPC UA Client functionality, no Server functionality so no license needed.
cMT-SVR-200/cMT-SVR-202 are the only products currently sold that require the purchase of an additional OPC UA license as they do not have the functionality built in.