Can you get a trade-mark for .doc, .pdf or other file extensions?  The makers of AutoCAD software are pursuing trade-mark protection over the file extension .dwg (referring to “drawing”), which is the file format for the AutoCAD software product. In the US case Autodesk, Inc. v. Dassault Systemes Solidworks Corp., 2009 WL 5218009 (N.D. Cal. December 31, 2009), the Court has made it clear that file extensions are functional and thus cannot be protected as trade-marks.

What about in Canada? Autodesk is also pursuing trade-mark protection for the DWG mark in Canada, and the application has been allowed.  No Canadian decisions have considered the specific question of claiming trade-mark rights over a file extension.  However, Canadian law accords with US law on the topic of functionality.  In the Supreme Court’s famous decision in Kirkbi AG v. Ritvik Holdings Inc., 2005 SCC 65 (CanLII), (the Lego case), the Court denied trade-mark protection for the shape of Lego building blocks on the grounds that the shape of the blocks is purely functional in nature, and thus cannot be protected as a trade-mark.

Calgary – 08:00 MT