In EU (European Union) there is a dispute around DWG as trademark. As a user that used Autodesk products a lot, I do associate DWG most with Autodesk and mainly the DWG file format. On the other hand I know of The Open Design Alliance (ODA) that makes the OpenDWG software library that can create, read and edit DWG files as well as other products that either uses OpenDWG and its DWGdirect or their own solution, some of them for many years. So if it's acceptable or not to use DWG as a trademark in EU time will tell.
Knowledge Base Software (Pty) Limited and SolidWorks Corporation are opposing the registration of DWG by Autodesk, Inc. and Autodesk, Inc. is opposing registration of DWGGATEWAY and DWGEDITOR by SolidWorks Corporation.
For DWG™ trademark guidelines, see Paragraph 7, under Guidelines for Use