Clarity has been restored to an area of copyright law after the Court of Appeal’s ruling on Dan Brown’s The Da Vinci Code.

Although the appeal court agreed with trial judge Mr Justice Peter Smith’s conclusions, it felt the need to re-state the correct approach to copyright infringement claims following the hasty publication of Smith J’s “long and complicated” judgment.

Smith J. ruled that novelist Brown had not breached copyright in The Holy Blood and The Holy Grail (HBHG) – an earlier book by three authors, including claimants Michael Baigent and Richard Leigh.

In a claim against publisher Random House, the claimants argued Brown had copied the majority of six chapters of The Da Vinci Code (DVC) from HBHG.

In particular, they claimed he had copied their book’s ‘central theme’, consisting of 15 elements, and that the copied material amounted to “a substantial part” of their book and, thus, an infringement of copyright under S.16 of the Copyright Designs and Patents Act 1988.

The first of the 15 elements, for example, was the following idea: Jesus was of royal blood, with a legitimate claim to the throne of Palestine.

Smith J. found that four of the 15 elements were not actually in both books, so no copyright infringement arose in relation to those.

As regards the other 11, he decided Brown had copied aspects of them from HBHG, but due to their generalised abstract nature, a “substantial part” of the book had not been copied.

The judge went out of his way to incorporate a cryptic message in his judgment, inspired perhaps by the books’ plots. The Court of Appeal agreed [28.03.07] with his conclusions, if not his approach.

Lloyd LJ clarified that the claimants’ ‘central theme’ was not a theme of HBHG at all. It was no more than a selection of features of HBHG, collated for the claimants’ “forensic purposes” rather than emerging from a fair reading of HBHG as a whole.

He emphasised: “Copyright does not subsist in ideas; it protects the expression of ideas, not the ideas themselves.”

Criticising Smith J’s ruling, he added: “The judgment is not easy to read or to understand. It might have been preferable for him to have allowed himself more time for the preparation, checking and revision of the judgment.”

Mummery LJ said a case by case approach was necessary. To prove infringement, it was insufficient for an alleged infringing work “simply to replicate or use items of information, facts, ideas, theories, arguments, themes and so on, derived from the original copyright work”.

He added: “No clear principle can be laid down on how or where to draw the line between the legitimate use of the ideas expressed and the unlawful copying of their expression. A judgment has to be reached by careful attention to the facts of each particular case.”

The Court of Appeal’s clarification of this area does not mean it is impossible to prove copyright infringement where one book has allegedly been heavily derived from another. But infringement will only be made out if there is clear copying of at least a “substantial part” of an earlier work with reference to the means of expression – as revealed by clues such as theme, incident and language – as opposed to mere copying of any ideas expressed.