Court Refuses to Extend Trade-mark Protection to File Extensions

In Autodesk, Inc. v. Dassault Systèmes Solidworks Corporation, the US District Court for the Northern District of California recently considered whether computer file extensions are entitled to trade-mark protection.

File extensions are the suffixes in computer file names, which generally comprise three or four characters. Their main purpose is to help computers identify the type of content that is in a computer file.

In this case, both parties produce software for 2D and 3D design and drafting. The plaintiff, Autodesk, Inc., produces a software product called AutoCAD, which uses files with the extension ".dwg." The defendant, Dassault, had released various products in association with its own trade-marks that incorporated the formative word element "DWG," and it marketed software that utilized or reverse-engineered the form of Autodesk's .dwg file format.