N.J DIFFUSION v GISELA MAYER (CFI, 1 August 2025)

Dhenne Avocats · 10 October 2026

Our analysis

Summary

By a decision of 1 August 2025 (UPC_CFI_363/2024), the Paris Local Division (Judges Lignières, presiding and judge-rapporteur, Gillet and Schilling) dismissed N.J Diffusion’s action for literal and equivalent infringement against Gisela Mayer based on EP 2 404 516, concerning a wig. The claim, which requires edges placed edge to edge, does not cover a cap whose edges overlap. The decision adopts a single function and effect criterion for equivalence and deals with the defendant’s costs claim where the claimant is in judicial reorganisation.

Facts and procedure

N.J Diffusion, proprietor of the patent in force in Belgium, Spain, France, Italy and Portugal, brought the action on 1 July 2024 against the « ELITE PREMIUM » range of wigs, whose tulle and monofilament cap is joined by a translucent non-slip strip. It sought, among other things, EUR 300,000 by way of interim damages, injunctions, recall and publication. Reorganisation proceedings were opened against it on 5 June 2025 by the Paris Economic Activities Court (tribunal des activités économiques). The court-appointed administrator and creditors’ representative intervened and the proceedings resumed after Gisela Mayer lodged its claim (paragraph 6). Equivalence was only added, in the alternative, in the reply (paragraph 68).

The applicable law

The Division applies Articles 24, 25, 26, 33 and 69 UPCA, Article 69 EPC and its Protocol on Interpretation, and Rules 9.2, 13.1(n), 36 and 220.1(a) RoP. On costs, it applies French law as the law of the State of opening (Article 7 of Regulation (EU) 2015/848) and Articles L. 622-7, L. 622-17 and L. 622-22 of the French Commercial Code (paragraphs 86 to 91).

Question

Can a claim limited to edges placed edge to edge be infringed, literally or by equivalence, by a cap with overlapping edges, and how should the defendant’s costs claim be handled where the claimant is in reorganisation proceedings?

Decision

The action is admissible: the statement of claim sets out, if briefly, why there is infringement, and Rule 13.1(n) RoP only requires a claim construction « where appropriate » (paragraphs 11 to 15). Although the description discloses two methods of assembly, the claim retains only the edge-to-edge method, which defines the scope of protection (paragraphs 40, 59 and 60). Features 1.4, 1.5 and 1.6a are present, but the products’ edges overlap: feature 1.6 is missing, and the dependent and process claims are not infringed either (paragraphs 51 to 66). The equivalence case raised in the reply is admitted, since it adapts the strategy to the defence, which could answer in its rejoinder (paragraph 70). The Division declines the four-question test of The Hague Local Division and adopts a single criterion from a harmonised approach: do the substitute means perform essentially the same function to achieve essentially the same effect (paragraphs 76 to 81)? The strip in the products covers the seams rather than joining the fabrics, so equivalence is not made out (paragraphs 82 to 84). The costs claim, which arose after the opening but is not useful to the proceedings, remains subject to the collective procedure: the payment request is inadmissible against the claimant and unfounded against the insolvency officers, absent any specific fault, the claim is entered in the liabilities at EUR 50,000 (paragraphs 86 to 94).

Key points for practice

• The wording of the claim prevails over the description: an embodiment described but not claimed cannot be brought back through construction.
• An equivalence argument raised in the reply may be admitted if it responds to the defence and the opponent has been able to answer it.
• The single function and effect criterion, preferred to The Hague Local Division’s four-question test, reflects the search for a harmonised approach to equivalence.
• Practical point: against a claimant in reorganisation proceedings, the defendant obtains entry of its costs claim in the liabilities, not an order for payment.

Provisions applied

Agreement on a Unified Patent Court

Arts 24, 25, 26, 33 and 69

Rules of Procedure

Rules 9.2, 13.1(n), 36 and 220.1(a)

European Patent Convention

Art. 69

Case law cited

AGFA v Gucci, Hamburg Local Division, 30 April 2025, Mannheim Local Division, 6 June 2025 (UPC_CFI_471/2023), Brussels Local Division, 17 January 2025 (UPC_CFI_376/2023) and order of 8 July 2024, The Hague Local Division, 22 November 2024 (UPC_CFI_239/2023), Court of Appeal, 21 November 2024 (UPC_CoA_456/2024), Court of Appeal, UPC_CoA_335/2023 and UPC_CoA_1/2024

Prepared by Dhenne Avocats from the official decision, consulted on 10 October 2026. The database is updated every week, on Friday. Only the official text is authoritative.