Foreign-Judgment Issue Estoppel Is Governed by the Lex Fori, Not Rome II

1. Introduction

This appeal established that the preclusive effect of a foreign judgment—particularly whether it creates an issue estoppel in English proceedings—is governed by the law of the forum, not by the law applicable to the underlying non-contractual claim under Regulation (EC) No 864/2007 (“Rome II”).

The dispute arose from competing online gambling products described as “crash games”. The appellants, collectively referred to as Aviator, alleged ownership of copyright in an “Aviator Image” and an associated aeroplane device. They claimed that Spribe’s competing game infringed those copyrights in the United Kingdom, Gibraltar and numerous Berne Convention countries. Spribe denied copyright ownership and copying and brought counterclaims involving trade marks, passing off and copyright.

Aviator had previously succeeded against Spribe in Georgian proceedings concerning a Georgian trade mark. It argued that findings made in those proceedings prevented Spribe from re-litigating questions of copyright subsistence, ownership and copying in England.

The central question was therefore not which law governed copyright infringement—the parties accepted that Article 8(1) of Rome II generally applied the law of each country for which protection was claimed—but which law determined whether the Georgian judgments created an issue estoppel.

2. Summary of the Judgment

Arnold LJ, with whom King LJ and Miles LJ agreed, allowed Aviator’s appeal and reversed the decision of the Deputy High Court Judge.

The Court held that:

• The issue must be characterised as one concerning the effect of a prior foreign judgment, rather than liability for copyright infringement.
• The recognition and preclusive effect of a foreign judgment are governed by the law of the receiving court—the lex fori.
• Rome II governs specified non-contractual obligations; it does not govern the effect of prior judgments.
• Article 15(a), which provides that the applicable law governs the basis and extent of liability, does not extend to issue estoppel merely because estoppel may affect whether liability can be proved.
• If the subject were within Rome II at all, it would fall within the exclusion for “evidence and procedure” in Article 1(3), rather than within Article 15.
• It was consequently unnecessary to decide whether Articles 16 or 26—overriding mandatory provisions and public policy—could produce the same result.

The Court did not decide whether the Georgian judgments actually satisfied the requirements for an English-law issue estoppel. It determined only the governing-law question.

3. The Governing Principle

Whether a foreign judgment has a preclusive effect in English proceedings, including whether it creates an issue estoppel, is governed by English law as the lex fori. That question falls outside Rome II; alternatively, it is excluded by Article 1(3) as a matter of procedure.

This principle applies even where the substantive claims are governed by multiple foreign laws under Article 8(1). Thus, German law may govern the German copyright claim and another national law may govern a claim relating to another territory, but English law determines the effect which the English court gives to the earlier Georgian judgment.

4. Legal Reasoning

4.1 Characterisation of the issue

The decisive step was identifying the true nature of the question. Spribe characterised it as part of the determination of liability for copyright infringement. Aviator characterised it as concerning the legal effect of an earlier judgment.

The Court accepted Aviator’s characterisation. Issue estoppel is not peculiar to copyright, intellectual property or tort law. It is a general doctrine controlling repetitive litigation. The same is true of cause of action estoppel, merger and abuse of process.

Although English domestic law describes res judicata as a rule of substantive law, that description did not control its classification for conflict-of-laws purposes. In the broader, autonomous context of private international law, the doctrine regulates how a court conducts adjudication and how it treats an earlier judgment. It is therefore “adjectival” rather than part of the substantive law defining the parties’ underlying rights and obligations.

4.2 The limits of Rome II

Rome II does not regulate every legal issue arising in litigation. It selects the law applicable to certain non-contractual obligations. Contractual obligations are addressed by Rome I, while recognition and enforcement of judgments are dealt with, where applicable, by instruments such as the Brussels I Regulation.

Article 8(1) selects the law of the country for which intellectual-property protection is claimed. That law determines substantive questions such as copyright subsistence, ownership where relevant to infringement, copying, available defences and remedies. It does not determine how an English court should treat an earlier foreign judgment.

4.3 Article 15 does not convert procedural effects into substantive law

Spribe relied particularly on Article 15(a), under which the applicable law governs the “basis and extent of liability”. It argued that because an issue estoppel could determine whether a liability issue remained open, the applicable copyright law must also determine the estoppel.

The Court rejected that reasoning as confusing a rule’s nature with its practical effect. Many procedural or adjudicative rules can affect the outcome of a liability dispute, including rules about pleadings, admissions and evidence. That consequence does not make them part of the substantive law governing liability.

The travaux préparatoires reinforced this conclusion. They showed that Article 15 was intended to cover intrinsic and extrinsic components of substantive liability, such as fault, causation, strict liability, exemptions and limitations—not the recognition or preclusive effect of judgments.

4.4 Relationship with Article 1(3)

The Court’s primary conclusion was that foreign-judgment preclusion falls outside Rome II altogether. Its alternative conclusion was that, if the subject came within the Regulation’s general field, it was excluded by Article 1(3), which states that Rome II does not apply to evidence and procedure, subject to specified exceptions.

The Court therefore avoided treating Article 15 expansively and Article 1(3) narrowly. Both provisions must be interpreted according to their wording, purpose and context.

4.5 The structure of European private international law

Recognition and enforcement of judgments occupy a distinct field from choice of law. Under the Brussels I framework, judgments of Member State courts receive prescribed recognition, but matters not harmonised remain governed by the receiving state’s law.

Although Brussels I no longer forms part of domestic UK law following Brexit, its position within the European legislative scheme remained relevant to interpreting Rome II. Rome II was not intended to duplicate or displace the separate rules governing recognition and enforcement.

4.6 Coherence and practical consequences

The Court also considered the practical anomalies in Spribe’s position:

• Different estoppel laws could apply to different causes of action involving the same previously decided issue.
• A single multi-territorial copyright action could require separate estoppel analyses under numerous national laws.
• Even the effect of a prior English judgment might be determined by foreign law selected under Rome II.

Applying the lex fori avoids those anomalies. One law governs the preclusive effect of the earlier judgment regardless of the underlying causes of action or the territories in which copyright protection is claimed.

5. Precedents Cited

5.1 English law on res judicata and issue estoppel

Virgin Atlantic Airways Ltd v Zodiac Seats UK Ltd [2013] UKSC 46, [2014] AC 160 supplied the modern taxonomy. Cause of action estoppel prevents re-litigation of a cause of action already finally determined, while issue estoppel prevents re-litigation of an issue necessarily decided in earlier proceedings. The Court of Appeal also relied on its distinction between res judicata, described domestically as substantive law, and abuse of process, which controls the exercise of procedural powers.

Associated Electric and Gas Insurance Services Ltd v European Reinsurance Co of Zurich [2003] UKPC 11, [2003] 1 WLR 1041 supported the proposition that pleading an estoppel is a means of enforcing rights arising from an earlier judgment or award.

Hulley Enterprises Ltd v Russian Federation [2025] EWCA Civ 108, [2026] KB 1 explained that once an issue is conclusively determined, contrary evidence is irrelevant and cannot be adduced. It also supported the historical application of the lex fori to the effect of foreign decisions.

Gol Linhas Aereas SA v MatlinPatterson Global Opportunities Partners (Cayman) II LP [2022] UKPC 21, [2023] Bus LR 1305 identified the requirements for an issue estoppel based on a foreign judgment: the judgment must qualify for recognition, the parties or their privies must be the same, and the issue must be identical.

Henderson v Henderson (1843) 3 Hare 100 was used to distinguish issue estoppel from the broader abuse-of-process doctrine preventing parties from advancing matters which should properly have been raised earlier.

5.2 Historical authority for applying the lex fori

Castrique v Imrie (1869-70) LR 4 HL 414, Carl Zeiss Stiftung v Rayner C Keeler Ltd (No 2) [1967] 1 AC 853, The Sennar (No 2) [1985] 1 WLR 490, Owens Bank Ltd v Bracco [1992] 2 AC 443 and PJSC National Bank Trust v Mints [2022] EWHC 871 (Comm), [2022] 1 WLR 3099 demonstrated the longstanding English conflicts rule that the effect of a foreign judgment is determined by English law as the law of the receiving forum.

5.3 Recognition and enforcement

Martin v Nadel [1906] KB 26, Société Eram Shipping Co Ltd v Cie Internationale de Navigation [2003] UKHL 30, [2004] 1 WLR 260, Yukos Capital Sarl v OJSC Rosneft Oil Co (No 2) [2012] EWCA Civ 855, [2014] QB 458 and London Steam-Ship Owners' Mutual Insurance Association Ltd v Kingdom of Spain [2024] EWCA Civ 1536, [2025] 1 WLR 3011 confirmed that recognition and enforcement are inherently governed by the receiving legal system, subject to any applicable treaty or legislative regime.

5.4 Characterisation authorities

Raiffeisen Zentralbank Österreich AG v Five Star General Trading LLC [2001] EWCA Civ 68, [2001] QB 825 required characterisation in a “broad internationalist spirit”, rather than through narrowly domestic categories. In re Harrods (Buenos Aires) Ltd [1992] Ch 72 warned against framing the characterisation question in a way that assumes the answer.

Case C-176/25 IU v BT [EU:C:2026:785] illustrated that different issues within one intellectual-property action may be governed by different choice-of-law rules. A contractual question concerning an assignment could fall under Rome I even though the infringement claim itself fell under Rome II. This supported an issue-by-issue approach.

5.5 Res judicata as part of domestic procedural law

Case C-234/04 Kapferer v Schlank & Schick GmbH [2006] ECR I-2606, Case C-2/08 Amminstrazione dell'Economia e delle Finanze v Fallimento Olimpiclub Srl [2009] ECR I-7520, Case C-40/08 Asturcom Telecommunications SL v Nogueira [2009] ECR I-9602 and Joined Cases C-370/17 and C-37/18 Caisse de retraite du personnel navigant professionnel de l'aéronautique civile (CRPNPAC) v Vueling Airlines SA [EU:C:2020:260] showed that EU law generally treats res judicata as part of domestic procedural rules.

5.6 Brussels I and the effects of judgments

Case 145/86 Hoffmann v Krieg [1988] ECR 645, Case C-456/11 Gothaer Allgemeine Versicherung AG v Samskip GmbH [EU:C:2012:719] and Case C-567/21 BNP Paribas SA v TR [EU:C:2023:452] established that a recognised Member State judgment must in principle receive the same effects in the receiving state as in the state of origin.

Case C-379/17 Società Immobiliare Al Bosco Srl [EU:C:2018:806] confirmed that matters not harmonised by Brussels I remain subject to the receiving state’s procedural law. Case C-568/20 J v H Ltd [EU:C:2022:264] further established that, absent EU harmonisation concerning third-state judgments, Member States may apply their own national rules.

5.7 The boundary between substance and procedure under Rome II

Nicholls v Mapfre España Cia de Seguros y Reaseguros SA [2024] EWCA Civ 718, [2025] 1 WLR 660 and Actavis UK Ltd v Eli Lilly and Co [2015] EWCA Civ 555, [2025] Bus LR 1068 rejected both an excessively broad and an excessively narrow reading of the procedural exclusion. The provisions must instead be interpreted contextually.

Wall v Mutuelle De Poitiers Assurances [2014] EWCA Civ 138, [2014] 1 WLR 4263 supported the proposition that Rome II seeks uniformity in applicable substantive law, not identical litigation outcomes in every forum.

The reference to Hasbro Consumer Products Licensing Ltd v Công Ty Tnhh Đầu Tư Công Nghệ Và Dịch Vụ Sconnect Việt Nam [2026] EWHC 1546 (Ch) concerned the separate presumption that unproved foreign law is the same as English law. It did not materially determine the appeal because Spribe agreed that the presumption could be used.

6. Complex Concepts Simplified

Lex fori

The law of the court hearing the case. Here, it is English law.

Lex loci protectionis

The law of the country for which intellectual-property protection is claimed. A German copyright claim is ordinarily governed by German copyright law.

Lex causae

The substantive law selected to govern a particular claim or issue.

Res judicata

A collective term for doctrines preventing matters already judicially determined from being litigated again.

Issue estoppel

A rule preventing a party from re-litigating a specific issue that was necessarily and finally decided between the same parties or their privies.

Cause of action estoppel

A stricter bar preventing the same cause of action from being brought again after final determination.

Adjectival law

Rules governing adjudication, procedure and the enforcement of substantive rights, rather than the rights and liabilities themselves.

Recognition of a foreign judgment

The process by which the forum accepts that a foreign judgment has legal effect. At common law, the foreign court must have had jurisdiction and its decision must be final and conclusive on the merits.

7. Impact

The decision is particularly important for multi-territorial intellectual-property litigation. English courts may adjudicate claims governed by several national copyright laws, but they need not apply a different national law to the preclusive effect of the same earlier judgment. English law supplies a single, coherent framework.

The principle is not confined to intellectual property. Its reasoning extends to non-contractual claims generally because it rests on the classification of judgment preclusion, not on any special feature of copyright law.

The judgment may reduce foreign-law evidence and complexity where a party relies on an earlier judgment. However, it does not make foreign findings automatically binding. A party must still establish the English-law requirements for recognition and issue estoppel, including finality, competent jurisdiction, identity of parties or privies and identity of issues. The special-circumstances exception to issue estoppel may also remain relevant.

The ruling leaves untouched the substantive territoriality of copyright. Each infringement claim continues to be governed by the law selected under Article 8(1). Nor did the Court resolve the underlying copyright, trade mark, passing-off, gambling-licensing or counterclaim issues.

8. Conclusion

Aviator LLC & Ors v Spribe OÜ draws a clear boundary between the law governing substantive liability and the law governing the effect of earlier judgments. Rome II determines the substantive law applicable to territorial copyright claims, but it does not decide whether a foreign judgment prevents an issue from being litigated again.

By applying English law as the lex fori, the Court preserved the coherence of the law of recognition and avoided fragmented estoppel rules within multi-country litigation. The case is therefore an important authority on characterisation, the limits of Rome II and the treatment of foreign judgments in English private international law.