Unitary and National Patents: A Quest for Coherence

In Golconda, Magritte suspends dozens of identical men in bowler hats against the sky, floating side by side without ever meeting. The European patent landscape sometimes resembles that painting. Unitary patent, European patent in its classic form, and national patents coexist above the same market, applied by different judges, with no rule really organising their encounter. The question is not which title will outlive the others. It is how competing titles, construed by distinct judicial orders, can produce a coherent body of law.

Three Titles, Three Judges, One Text

Since 1 June 2023, the same invention can be protected by a Unitary Patent falling under the Unified Patent Court, by a classic European patent subject, during the transitional period, to a competence shared between the UPC and national courts, or by national patents that escape the new jurisdiction altogether. Article 83 of the Agreement organises this coexistence for seven years, renewable, and the opt-out allows the proprietor to remove its European patent from the UPC. Choosing a title has become choosing a judge, and choosing a judge has become choosing a method.

Yet these three routes apply, in essence, the same text. Patentability requirements flow from the European Patent Convention, infringement and its limits from largely harmonised provisions. Divergence therefore does not stem from the rule. It stems from the way the rule is read.

A common rule is not a common method

The experience of the last forty years demonstrates it: national courts applying an identical text have reached opposite results, on the scope of claims, on equivalents, on the weight given to the description. A common rule without a shared culture of interpretation produces a facade of harmony. Each judge reads the same text with his own reflexes, and Magritte's men keep floating side by side without seeing one another.

This is precisely the ground chosen by the Enlarged Board of Appeal of the EPO in its decision G 1/24 of 18 June 2025. The claims remain the starting point and the basis for assessing patentability, but the description and drawings shall always be consulted to interpret them, and not only where the claim appears ambiguous. The Enlarged Board discarded the restrictive reading that reserved the description for cases of unclarity in the claim language.

G 1/24, a voluntary alignment

The most remarkable feature is not the order, it is the reasoning. The Enlarged Board expressly referred to the case law of the UPC Court of Appeal, which has held since 2024 that the description and drawings always serve as explanatory aids for the interpretation of the claims, and it chose to converge with it. No provision required it to do so. The EPO does not answer to the UPC, and the UPC does not bind the Boards of Appeal. Convergence came from a choice, the choice of avoiding a system in which grant and litigation rest on two different readings of the same title.

The movement continues. Referral G 1/25, on the adaptation of the description to amended claims, prolongs the same debate on the role of the description, and its outcome will tell whether the alignment initiated by G 1/24 extends to the drafting of the patent itself.

Coherence through circulation, not uniformity

Does Europe then need an institutional reform, a supreme patent court, a new hierarchy? Nothing is less certain. Uniformity imposed from above would require a treaty revision that no one is carrying. Coherence can come from elsewhere: from the effective circulation of case law between the orders, from its translation, from its accessibility, from the dialogue between judges, academics and practitioners. G 1/24 is the demonstration: convergence happened because the UPC's case law was known, read and discussed in Munich.

That case law must, however, actually circulate. The UPC now issues several decisions a day, in several languages, and following them systematically has become a condition of coherence as much as a tool of litigation strategy. This is the purpose of the recension work we carry out with our UPC case law database, which covers all decisions handed down since the Court opened.

What this changes in practice

For the litigator, three consequences. First, claim construction is now argued everywhere with the description in hand, before the EPO as before the UPC, and the argument drawn from a claim said to be clear in itself has lost its footing. Second, cross-forum monitoring becomes indispensable: a divergence between a UPC division, a Board of Appeal and a national court is an opportunity or a risk depending on which side of the bar one stands. Third, the title strategy, between the Unitary Patent, the European patent with or without opt-out and national routes, must factor in the interpretive culture of each forum, and no longer only its speed or its cost.

The European landscape will remain populated by competing titles. The question is whether the men in bowler hats will keep floating without seeing one another, or whether they will end up talking. G 1/24 suggests the conversation has begun. The firm supports patentees and defendants in these disputes, before the UPC as before the French courts, notably as correspondent in France for patents and the UPC. Contact us.

This article is an original and substantially updated adaptation of an analysis by Matthieu Dhenne first published on the Kluwer Patent Blog on 20 June 2025: Golconda and the Quest for Coherence: Unitary and National Patents in the European Landscape.