Aviator LLC v Spribe OÜ: English law governs issue estoppel from foreign judgments, Court of Appeal rules

English law, rather than the law applicable to each underlying infringement claim under the Rome II Regulation, governs whether a foreign judgment gives rise to an issue estoppel, the Court of Appeal has held. Reversing a High Court decision, the court allowed an appeal in Aviator LLC & Ors v Spribe OÜ [2026] EWCA Civ 1224, with Arnold LJ giving the leading judgement and King LJ and Miles LJ agreeing.

The dispute

The litigation concerns competing online "crash games". The claimants allege that Spribe's game copies an image and aeroplane device in which they claim copyright, and sue for infringement in the UK, Gibraltar and all Berne Convention countries other than Georgia. Spribe counterclaims for trade mark infringement and passing off.

The claimants relied on Georgian proceedings in which they successfully challenged Spribe's Georgian trade mark on the basis that its use would infringe their copyrights. They argued that issue estoppels flowed from that outcome on subsistence, ownership and copying. It was common ground that Article 8(1) of Rome II makes the law of each protecting country apply to the infringement claims. The question was whether that extended to the effect of the Georgian judgment.

Michael Tappin KC, sitting as a deputy High Court judge, had accepted Spribe's argument that it did. Arnold LJ reached the opposite conclusion.

Characterisation

Arnold LJ treated the issue as one of characterisation, requiring a "broad internationalist spirit". He agreed with the claimants that the issue concerns the effect of a prior judgment, not liability for copyright infringement. Issue estoppel, cause of action estoppel, abuse of process under Henderson v Henderson and merger are general doctrines, applying whatever the nature of the underlying claim. They belong to adjectival law, regulating how proceedings are conducted and substantive law enforced, rather than to substantive law.

That accords with Court of Justice of the European Union case law, which treats res judicata as a domestic procedural rule.

Scope of Rome II

The effect of foreign judgments is a field governed by the law of the receiving state. Within the EU scheme, recognition and enforcement fall to the Brussels I Regulation, which leaves most matters to national procedural law, and Rome II is to be read consistently with it. Its aims of predictability and uniformity do not reach issues outside its scope.

Spribe did not say the issue fell within any limb of Article 15, relying instead on Article 15(a), which places the basis and extent of liability under the applicable law. Arnold LJ said this confused the nature of a rule with its effect. A rule is not part of the law governing a non-contractual obligation merely because it may influence whether liability is established. The travaux préparatoires confirmed that Article 15 concerns substantive law.

Applying Nicholls v Mapfre, which requires neither a broad nor a narrow reading of Articles 1(3) and 15, he concluded that the issue lies outside Rome II altogether. If wrong, it would fall within Article 1(3), which excludes evidence and procedure, rather than Article 15.

Consequences

Practical considerations pointed the same way. Spribe's approach would apply different laws to issue estoppel depending on whether a claim was governed by Rome II, and potentially to different causes of action involving the same issue. It would even mean that the effect of a prior English judgment was governed by a foreign law. Applying the lex fori produces coherence whatever the claim or the judgment's origin.

It was therefore unnecessary to consider the alternative arguments based on Articles 16 and 26, and the appeal was allowed.