Autodesk's efforts to monopolise the ".dwg" file extension via a pending US “DWG” word mark application (No. 78 852 798) claiming all kinds of "computer software", have, even though the USPTO has not yet issued a final refusal to register the mark, meanwhile led to the satisfactory result that file extentions cannot be trademark protected in the US (see, e.g., here, here, or my earlier post).
Even though Autodesk had to disavow the US lawsuit Autodesk vs DS SolidWorks that, as fas as Autodesk is concerned, anyone in the world is free to use “.dwg” as a file extension (cf. doc 241, filed on December 31, 2009; see also here), a file extension is in fact to be considered descriptive and/or generic due to its functional use, while it is a fundamental rule of US trademark law that trademark protection is not issued on symbols or marks that are entirely functional.
In Europe, Autodesk applied for a Community Trademark "DWG" (No. 004703641) claiming, inter alia, "Computer software; computer aided design software; software developer tools; software for sharing information in a secure environment; downloadable software", which meanwhile has been withdrawn after two oppositions filed by opponents "Knowledge Base Software (Pty) Ltd" and "DS SolidWorks Corporation" and a subsequent appeal.
In Germany, two parallel “DWG” word marks are currently pending - No. 3020090602751 and No. 3020090276943 - the latter being a conversion of the withdrawn CTM registration -, both claiming computer software, CAD software or the like, which may, if granted, potentially be used to prohibit usage of the “.dwg” file extension in Germany.
However, even though Autodesk's respective disavowal in the US lawsuit is irelevant in Germany, Autodesk's German trademarks most likely cannot be used to obstruct using “.dwg” file extensions, since appropriate legal measures and arguments exist to both attack a potentially granted mark and, if necessary, defend against an infringement threat.
File extensions are technical indications of a file's format and, as such, cannot be registered due to absolute grounds for refusal according to § 8 II MarkenG (German Trademark Act), since, in my opinion, such signs are devoid of any distinctive character (§ 8 II, 1) and/or consist exclusively of indications which may serve to designate the kind, intended purpose or other characteristics of the claimed goods or services (§ 8 II, 2), in analogy to the related US doctrine.
Autodesk may still argue that, according to § 8 III MarkenG, “DWG” has established itself in affected trade circles as distinguishing sign such that possible absolute grounds for refusal have been overcome. In fact, Autodesk has already argued along this line in the above-mentioned US lawsuit Autodesk vs DS SolidWorks (cf. doc 1, Complaint, filed on September 19, 2008; see also here) by asserting that design professionals would recognize “DWG” as the name of Autodesk's proprietary technology and file format (doc 1, §§ 9, 10).
But Autodesk has also acknowledged the importance of interoperability between AutoCAD and third-party programs, for which reason technology transfer and licensing programs have been set up (doc 1, §§ 14, 15) by Autodesk, such as the “Autodesk Developer Network” or the RealDWG” licensing program. Autodesk further acknowledges that “competitors also have incorporated a reverse-engineered forms of Autodesk's proprietory DWG file format into their software” and that “limited use of .dwg solely as a filename extension may be necessary to achieve a level of interoperability of Autodesk programs” (doc 1, § 17).
However, design experts and CAD users certainly got used to the fact that file extensions generally are not primarily associated with a file's or a software's origin but rather with its technical format. It is, for instance, well known that even though formats like “.doc” or “.pdf” may originally have been developed by Microsoft or Adobe Systems, files carrying such extensions do not necessarily have to be generated by software products of these firms, even though at least the “.doc” format is still proprietary. Computer users would consider a file extension to have no origin-designating function, but rather regard it as a link to technical properties of the file in a merely descriptive and functional way. And in fact, besides the authorised and/or licensed usage of “.dwg” files, there exist many more software products from numerous origins not authorised or controlled by Autodesk for converting or otherwise manipulating “.dwg” files.
For these reasons and when considering the extensive evidence filed with the letter of protest of March 16, 2010 in the parallel US registration proceedings, it appears highly doubtful whether (i.) “DWG” really has established itself in affected trade circles as distinguishing sign for Autodesk's products and technology and whether (ii.) using the file extension “.dwg” represents a relevant use of Autodesk's trademark at all.
As a counter measure a request for cancellation because of absolute grounds for refusal () according to § 54 MarkenG may be filed with the GPTO within a period of 10 years from the date of registration (§ 50 II MarkenG). Alternatively, an immediate third party submission could also be considered.
For the same reasons, as a defensive measure, the prospect of success of a trademark infringement action against usage of the “.dwg” file extension based Autodesk's potential German “DWG” trademarks would also be rather limited, since such claims may be tackled based on § 23 MarkenG, which limits the scope of a registered trademark in that (i.) signs identical with or similar to the registered trade mark may be used as indications concerning characteristics or properties of the claimed goods or services (§ 23, No 2), in particular its kind, quality, intended purpose, value or the like, and (ii.) the trademark may be used where it is necessary to indicate the intended purpose of a product or service (§ 23, No 3), provided such use is not contrary to accepted principles of morality.