High Court refuses to allow representative action to be brought on behalf of copyright owners in IP case

The High Court has once again refused to allow a claim to be brought as a representative action under CPR 19.8, this time in the IP context. The court rejected an attempt to bring a claim on behalf of copyright owners who had exclusively licenced their works to the Getty Images Group (another claimant in the action) and whose works were said to have been used in training the defendant's AI model, Stable Diffusion: Getty Images (US) Inc v Stability AI Ltd [2025] EWHC 38 (Ch).

The court referred to Emerald Supplies Ltd v British Airways PLC [2010] EWCA Civ 1284 (considered here), in which the Court of Appeal held that, to establish that the represented parties all have the "same interest" in the claim (as required under CPR 19.8), it must be possible at all stages of the proceedings, and not just when judgment is given, to say whether any particular person has that interest and therefore qualifies for membership of the class. In that case, it was held that the requirement was not satisfied because the class definition included reference to whether prospective class members (purchasers of air freight services) had paid prices which were inflated by the alleged price-fixing cartel. That meant it could not be known who was a member of the class until the case on liability had been decided.

In the present case, the court applied Emerald Supplies in rejecting not only the claimant's initial formulation of the class definition, as those licensors whose copyright had been infringed – since that obviously depended on what the court needed to determine in the action – but also the alternative formulation as those licensors whose works had been used in training Stable Diffusion. The claimant argued that this was a question of objective fact, and moreover was within the defendant's own knowledge. But the court pointed out that there was no definitive list of the copyright works that had been used to train the AI, the defendant had only made limited admissions to the effect that “at least some” of the works had been used, and there was no consensus as to how (if at all) the question of which of the licensors' copyright works had been used to train the AI should be resolved. Accordingly, the class that was intended to be defined by reference to that question could not be identified. The court therefore held that it did not have jurisdiction to permit the representative action to be brought, or in any event it should decline to permit it as a matter of discretion.

The decision suggests that, in order to allow a representative action to proceed under CPR 19.8, it must be possible not only conceptually but in practical terms to determine whether a particular person falls within the class definition, and therefore has the "same interest" in the claim as the claimant bringing the action on their behalf.

For more information see this post on our Intellectual Property Notes blog.