World Programming Limited (WPL) created a runtime environment capable of executing programs written in the SAS language, without copying SAS source code, but by replicating functionality and compatibility with the language.
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SAS Institute sued for copyright infringement. The Court of Justice of the EU drew the line clearly: the functionality of a computer program, the programming language it uses and the file formats with which it operates are not protected by copyright.
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Copyright protects creative expression, source code, object code and manuals. It does not protect ideas, principles, methods or concepts, regardless of the form in which they are expressed in the program.
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This means that software interoperability and compatibility are permitted without the right holder’s consent. It is an important limit that favours competition and innovation in the IT industry.