I write a play and you direct it. In rehearsals, you change some of my lines. When it is performed, it is a huge success. So are you entitled to a share of my money?

Stones In His Pockets is a hit play that has had a run in the West End of London. But it has also given rise to a dispute over the ownership of copyright, and has been the subject of a recent court judgment.

Marie Jones is the author of the play. It was originally produced in Belfast and other parts of Ireland in 1996, where it was a moderate success. Pam Brighton was the director of that production. In 1999, Miss Jones to some extent rewrote the script and a new production was put on, directed by Miss Jones鈥� husband, which proved to be a huge success.

Miss Brighton claimed in court that many changes to the 1996 script had been made by her during rehearsals, so that she was the joint author of that script and therefore joint owner of the copyright in it. She claimed that Miss Jones was, therefore, in breach of her interest in the copyright when she created the 1999 script and thereafter exploited it.

Miss Brighton also claimed that Miss Jones had incorporated into the 1996 script a draft of the opening scenes to the play that Miss Brighton had written and had sent to Miss Jones for her to use if she wanted. Miss Brighton was the owner of the copyright in this draft opening, so Miss Jones needed a licence from Miss Brighton in order to use it.

Miss Brighton accepted that Miss Jones had an implied licence to use the draft opening in the 1996 script, but not to use it in the 1999 script and thereafter, when Miss Brighton and Miss Jones were no longer working together.

It is not difficult to see how this sort of dispute can arise in the construction industry, where many drawings and documents may be the result of a collaborative effort by more than one party, over a period of time, or be derived from earlier drafts that were prepared by different parties.

Where a consultant produces a drawing, the first ownership of copyright in the drawing usually vests in the consultant. However, if substantial input from the client or another party follows, there may be joint ownership of the copyright in subsequent versions of that drawing.

Alternatively, there may be more than one copyright underlying a work. This could arise where a consultant has obtained input for a design document or a report from a third party, such as a university department or a specialist company. Further, while there is no copyright in an idea as such, a work may be copied without a single sentence in the original work being used in the copy.

If substantial input from the client or another party follows, there may be joint ownership of the copyright

If a second author is to be counted as joint author, their contribution to the creation of the work must be significant 鈥� but it does not have to be equal to the contribution of the first author. On the other hand, a person can become a joint author even if they have not put pen to paper, but someone else has effectively written what they have created.

The court found that the contributions made by Miss Brighton in rehearsals were not sufficient to make her a joint author of the 1996 script.

However, the court found that Miss Jones had made sufficient use of Miss Brighton鈥檚 draft opening in the 1996 script for there to have been a degree of copying within the sense of copyright law. Although she had not used the exact words of Miss Brighton鈥檚 draft, she had used much of the plot. This meant the 1999 script also involved a degree of copying.

However, the court held that the implied licence from Miss Brighton to Miss Jones to use the draft opening continued until it was revoked by a letter from Miss Brighton鈥檚 solicitors in 2001. It covered the 1999 script and contracts entered into by Miss Jones for the exploitation of that script prior to the date of the revocation, but Miss Jones will need Miss Brighton鈥檚 consent to any future contracts to exploit the 1999 script.

Contracts in the construction industry normally seek to make ownership of copyright and the scope of the copyright licence clear, as between the parties to the contract, but the interests of other contributors may not always be covered.

Rachel Barnes is a partner in solicitor Beale & Company