From harmonisation to enforcement: patent law at the 2026 AIPPI World Congress

The 2026 AIPPI World Congress, held in Hamburg from 7 to 10 October, brought together IP practitioners, judges, industry representatives and academics from around the world. Its patent programme ranged from formal harmonisation work on divisional applications and double patenting to the practical challenges of cross-border litigation, contributory infringement and evidence.

Across the sessions, a common theme emerged: patent disputes are becoming increasingly international and technically complex, while the laws governing them remain territorially bound and only partly harmonised.

Divisionals and double patenting

A significant part of the Congress’s formal work concerned AIPPI’s study question on divisional applications and double patenting. Following discussion in dedicated Study Committee sessions and the patent plenary, AIPPI’s Executive Committee adopted a resolution.

The resolution recognises divisional applications as an important mechanism for protecting multiple inventions disclosed in a parent application but identifies a continuing need for harmonisation. Its central position is that an applicant should not be able to obtain more than one patent right in force for the same subject matter, for the same jurisdiction and from the same granting authority. It rejects using an obviousness standard to determine whether double patenting has occurred. It also rejects any restriction on the availability of divisional patents to address conduct by which a proprietor seeks to abuse a market position through the use of the patent system.

The debate highlighted the fact that harmonisation requires more than agreement on the desired outcome. It also requires agreement on which part of the legal system should deliver it.

Cross-border patent litigation

Blurring the Boundaries: Cross-Border Patent Litigation considered the growing jurisdictional reach of national and supranational courts. Its topics included the CJEU’s judgment in BSH Hausgeräte v Electrolux, an order of the District Court of the Western District of Texas preventing Onesta from pursuing injunctive relief against BMW in Germany based on its US patents, and forum selection. The panel included perspectives from the UPC, United States, United Kingdom, Brazil and China.

The examples discussed by the panellists illustrated that cross-border patent litigation is no longer simply a collection of parallel national cases. Courts are increasingly being asked to determine infringement of foreign rights or make orders affecting proceedings in other jurisdictions. As long-arm jurisdiction continues to develop, an unresolved question remains over how national courts will respond to another court asserting jurisdiction over acts within their territory. The possibility of anti-suit or similar relief means that an attempt to consolidate a dispute in one forum may generate further procedural litigation elsewhere.

The UPC’s continuing development

The Congress also included Everlasting Love? UPC Update, reflecting on the UPC’s maturation into a court with an increasingly substantial body of case law. The panel recognised the Court’s pragmatic approach to developing its procedures and that it is likely to refine them further through experience.

Expert evidence provided one example. The panel reflected on a two-day hearing at the Nordic-Baltic Regional Division in which the first day was directed to experts answering questions from the Court. This prompted debate over whether the UPC’s current procedural framework is well suited to more extensive hearing of expert evidence, or whether aspects of the system will need to evolve to enable this. The discussion suggested that the UPC will, with experience, develop its own approach rather than necessarily reproducing the practice of any single national court.

The panellists also considered the continuing presence of “national flavours” across the UPC’s divisions. Differences in practice remain visible, but they sit within a rapidly growing body of UPC jurisprudence through which more consistent approaches may emerge, guided by the Court of Appeal. The overall picture was of a court moving beyond its establishment phase: not with every procedural issue resolved, but with the flexibility to develop practical solutions as its case law deepens.

Contributory infringement

A separate comparative perspective was provided by Behind the Curtain: Contributory Infringement. The panel included Justice Sanjeev Narula of the High Court of Delhi, Sophie Lens of Altius, Dominic Adair of Bristows and Ewan Nettleton of Novartis, moderated by Meryl Koh of Drew & Napier. The session identified contributory infringement as an area in which significant differences between jurisdictions remain. 

The commercial problem is familiar: one party supplies a component, service or other means that facilitates infringement by another. However, legal systems differ over the necessary connection with direct infringement, the treatment of staple products, the supplier’s required knowledge and intent, and the territorial relationship between supply and ultimate use.

The comparison underlined that a supply arrangement that avoids secondary liability in one jurisdiction may not produce the same result elsewhere. Whilst there exists a large degree of harmonisation in Europe (which started with the 1975 Community Patent Convention and today is reflected in the UPC Agreement), not every country in Europe recognises contributory infringement and outside Europe, the landscape can be significantly different.

Looking ahead

Taken together, the sessions demonstrated the tension between increasingly international and complex patent disputes and the continuing diversity of the laws governing them.

AIPPI’s work remains valuable at both levels: developing common positions where harmonisation is achievable, and helping practitioners understand the differences that remain where it is not. The practical message is that an international patent strategy cannot simply take a domestic infringement case and extend it geographically. Whilst there is much common ground between jurisdictions, many differences remain and AIPPI’s objective to develop and improve the protection of IP remains ever relevant.