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Copyright Cannot Protect Functionality of Computer Programs

In what will be viewed as a serious blow to creators of computer software, the High Court has ruled that copyright in a computer program does not protect either the programming language in which it is written or its functionality from being copied by others.

The claimant was the developer of widely used analytical software (the software) which had been developed over a period of 35 years and was written in its own unique language. The defendants were the developers of an alternative product that sought to emulate the functionality of the software as closely as possible in the sense of trying to ensure that the same inputs would produce the same outputs.

There was no suggestion that, in creating its product, the defendants had access to the software’s source code or that any of the structural design of that code had been copied. The claimant’s plea of copyright infringement raised novel issues on the correct interpretation of EU Directive 2009/24/EC (the directive) that were referred to the European Court of Justice (ECJ) for a preliminary ruling.

In the light of the ECJ’s responses to a series of questions, the High Court ruled that the claimant’s case failed, save to a limited extent in respect of the defendant’s use of the claimant’s documentation to create a user manual for its product.

Although the software’s source and object codes were ‘forms of expression’ entitled to be protected by copyright, the court noted that the language in which the software is written had evolved considerably since its first creation in the same manner as a human language. Such modifications had not been planned and were not in accordance with any overall design.

The functionality of the software and the format of its data files also did not amount to forms of expression and were not protected by copyright for the purposes of the directive. The court went on to rule that those who obtain copies of computer programs under licence are entitled, without the authorisation of the copyright owner, to observe, study or test their functionality for the purpose of determining the ideas and principles which underlie their design.

On a correct interpretation of the directive, the reproduction of substantial elements of a computer program’s user manual was capable of constituting an infringement of copyright. However, the court concluded, “In short, copyright in a computer program does not protect either the programming language in which it is written or its interfaces, specifically its data file formats, or its functionality from being copied.”