Autodesk submits that its own statements and the Court’s Order mean simply what they say and nothing more: SolidWorks and any other party can use .dwg as a file extension when needed to achieve interoperability with the DWG format defined by Autodesk, and Autodesk has not attempted to state claims against such acts as they are functional uses of the letter string DWG.I've highlighted a phrase that could be read two ways: the DWG format as historically defined by Autodesk (and reverse engineered by anyone), or as licensed by Autodesk through its APIs only.*
Further, Autodesk accuses SolidWorks' parent Dassault Systemes of hypocrisy for wanting to trade mark the SAT file format, at the same time calling SAT "a de facto industry standard." Oops.
At the end, Autodesk's lawyer argues that SolidWorks wants the world to create versions of DWG that are incompatible with AutoCAD, and Autodesk does not want this to happen. This is an odd argument, for AutoCAD-incompatible .dwg files already exist (c.f. Generic CADD).
*) It does appear that my second definition is the more likely one: Autodesk is alright with competitors using .dwg files as long as they license APIs from Autodesk. Autodesk ceo Carl Bass has said his company will license its APIs to "everyone," but this doesn't cover the case of those who do not wish to pay licensing fees to Autodesk -- licensing fees that were lowered to match those of the ODA, and that might skyrocket should Autodesk be successful in shutting down the ODA.