Combining licenses involves editing your existing license file and copying into it the lines from your new license file. Do not configure a separate service for the new Autodesk product. There are some restrictions on which licenses can and cannot be combined in a single file.
Licenses that can be combined in a license file:
- Licenses for different releases of the same product, such as AutoCAD 2015 and AutoCAD 2016.
- Licenses for different Autodesk products, such as AutoCAD 2016 and Autodesk Revit 2016.
- Perpetual licenses and subscription licenses with multi-user access, even if the perpetual license is not on a maintenance plan
More information here.