Canada: 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.

Autodesk sued Dassault for trade-mark infringement under the Lanham Act (the US trade-mark legislation) and a host of other causes of action including unfair competition, false designation of origin, unfair or deceptive business practices, and deceptive, false and misleading advertising. Autodesk claimed that Dassault had misappropriated Autodesk's mark, DWG. Dassault argued that DWG was functional or generic, and therefore not entitled to trade-mark protection. Both parties moved for summary judgment on various motions. One of the main issues before the court was whether Autodesk had a valid common law trade-mark in respect of DWG.

At the summary judgment motions, Autodesk explicitly disavowed any claims against the use of .dwg as a file extension and sought trade-mark protection for only its use as a word mark. Specifically, Autodesk confirmed that it was only seeking to have the exclusive use of DWG in packaging, advertising and marketing materials. Autodesk's counsel, at the hearing, even went so far as to admit to the court that "any one in the world has a right to use DWG as a file extension" and that some competitor products actually would save files as .dwg files to render those files interoperable with AutoCAD products.

In ruling on the motions, the court partially sided with Autodesk. The court found that, in addition to the functional use, Autodesk had used DWG in a non-functional way (for example, in its product names). Therefore, the mark was not invalid on the grounds of functionality. The judge noted that Autodesk had expressly disavowed any ownership of any functional use of DWG, including the use of DWG as a file extension. This disavowal appears to have weighed heavily in the court's decision to not find the DWG mark invalid for functional reasons.

After the court's decision was rendered on the motions, Autodesk attempted to qualify its disavowal, claiming that it had only disavowed uses of .dwg as a file extension when such uses were necessary to achieve interoperability with its DWG file format. The court issued a further ruling, refusing to let Autodesk qualify its disavowal. The court found that ownership of file extension designations cannot be appropriated under the Lanham Act — file extensions are inherently functional, and functional uses cannot be trade-marked. It stated that computer programmers and computer users should be free to designate file extensions as they see fit, without the fear of infringing trade-marks.

The motions judge further opined that the purpose of the Lanham Act is to target unauthorized use of a trade-mark "in connection with a commercial transaction in which the trade-mark is being used to confuse potential consumers." In contrast, the purpose of file extensions is to indicate to a computer the type of file that is being handled. The court noted that "a computer is not a consumer," and its recognition of a file extension is not "in connection with a commercial transaction." In other words, the computer does not concern itself with the question of who made the file format. Therefore, whether on the grounds that a file extension connotes a "functional use" or a "non-trade-mark use," the court held that a file extension per se is not protectable under US trade-mark law.

In its decision, the court did recognize that computer users may associate a particular file extension with a specific vendor or manufacturer. However, the court found this association only incidental to the primary function of file extensions, namely to identify a file or file type. On the question of whether DWG was generic, the court declined to address the issue on summary judgment as there were genuine issues of material fact involved.

On the eve of trial, the parties settled the dispute and, as part of the settlement, they also came to agreement that DWG is a valid trade-mark owned by Autodesk.

McCarthy Tétrault Notes

While the court found that there are no trade-mark rights enforceable in file extensions per se, the specific characters in a file extension may be protected as a word mark, for instance, for use in packaging, advertising and marketing materials of a corresponding software product.

In Canada, a recently allowed application by Autodesk, Inc. exists for the word mark DWG for use in association with "computer programs and software in the field of computer aided design and instruction manuals sold as a unit." It will be interesting to see how a Canadian court would rule on the issue if Autodesk were to assert its trade-mark rights against the use of .dwg as a file extension in Canada. The expectation is that a Canadian court would not protect DWG as a trade-mark when the mark is used as a file extension because the reverse would grant Autodesk Inc. a monopoly on functional elements of their wares, thus preventing others from creating computer files that could work with Autodesk Inc.'s software. This is consistent with the longstanding rule in Canada that anything that is primarily functional cannot be the subject of trade-mark protection.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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