‘The Defendant, World Programming Ltd ("WPL"), perceived that there would be a market demand for alternative software which would be able to execute application programs written in the SAS Language. WPL therefore created a product called World Programming System or WPS to do this. In developing WPS, WPL sought to emulate much of the functionality of the SAS Components as closely as possible in the sense that, subject to only a few minor exceptions, it tried to ensure that the same inputs would produce the same outputs. This was so as to ensure that WPL's customers' application programs executed in the same manner when run on WPS as on the SAS Components. There is no suggestion that in doing so WPL had access to the source code of the SAS Components or that WPL have copied any of the text of the source code of the SAS Components or that WPL have copied any of the structural design of the source code of the SAS Components.’In the judge’s view replicating the functionality of the SAS software did not infringe copyright, but WPL’s manuals did – though you would expect the manuals to bear some resemblance to the SAS manuals there was a degree of similarity in the language that went beyond the inevitable.
Programming languages: are they idea or expression?
Interfaces: the Software Directive makes some concessions for the fact that computer programs need to interface with each other. But are interfaces completely unprotected by copyright?
Functions: copyright may protect not just the software’s source code but also its design. To what extent can software be eligible for the type of copyright protection that is extended to the plot of a novel? How far can functionality be equated with design/organization?