Mr Harris was employed by Visusoft Limited from January 2005 to March 2006. Prior to entering this employment, Mr Harris had developed a software programme called Risc 5. The copyright in this software was never assigned to Visusoft but Mr Harris, in conjunction with other Visusoft employees, further developed the programme, which was subsequently marketed by Visusoft as Datapos. Following the termination of Mr Harris’ employment in 2006, he was required to remove all copies of source code and other components of the Datapos software from his personal computers, which he confirmed that he had done in a letter to the plaintiff. After leaving this employment, Robert Harris developed and marketed software called Risc 7. Visusoft alleged that Risc 7 was substantially copied from its Datapos programme.

There was no dispute that Robert Harris had expended skill and labour on behalf of Visusoft in developing Datapos and, as such, the plaintiff had copyright in elements of the Datapos programme. Expert evidence tendered by both the plaintiff and the defendant showed that elements of Datapos were incorporated in Risc 7 and, indeed, it was subsequently discovered that Robert Harris had retained a version of Datapos, which he deleted only after the litigation had commenced. There was conflicting evidence as to the degree of similarity between Datapos and Risc 7 and Murphy J had to decide whether the evidence showed that Datapos formed a substantial part of Risc 7. His Honour quoted with approval the decision of Pumfrey J in Cantor Fitzgerald International v Tradition (UK) Limited [2000] RPC 95 which held that it would be simplistic to regard every part of a computer programme as “substantial”, even if every part is essential.

Murphy J was not satisfied that Datapos constituted a substantial part of Risc 7. Despite parts of the source code being similar, he found that the evidence did not support the conclusion that there were common ancestry files, particularly as code can be generated by computer. In particular, two of the expert witnesses could only conclude that it was not impossible for Risc 7 to be a copy of Datapos and the judge held that this assertion fell short of positive evidence.

As a result, the Court’s decision did not ultimately turn on copyright infringement but rather it found that Mr Harris had breached his original agreement and subsequent undertaking given to Visusoft concerning deletion of the Datapos software and code. The Court accordingly refused to find that Risc 7 infringed Visusoft’s copyright in Datapos, but that it was entitled to damages for breach of contract. It will be interesting to see whether the damages finally awarded by the Court are equivalent to an amount which might otherwise be awarded for copyright infringement damages.