CD Milan, October 9, 2026, Central Revocation Action, UPC_CFI_1587/2025

The party alleging added matter must identify, by means of a specific comparison, the subject-matter of the original disclosure that is said to have been extended in the later
application or divisional patent (Art. 65(2) UPCA, Art. 123(2), 138(1)(c) EPC).

A large number of embodiments and theoretical combinations in the application as filed does not, by itself, establish added matter. The claimant must identify which subject-matter in the claim extends beyond the original disclosure.

Procedural fairness requires each party to plead its grounds clearly (Recital 5 of the Preamble to the RoP). The Court may neither cure deficiencies nor supplement them of its own motion, as this would compromise its impartiality.

Where the contribution lies in identifying a physiologically or pathologically distinct patient subgroup, the patent must make it credible that the product is suitable for the claimed use in that subgroup. The exact therapeutic dose need not appear in the claim, provided the skilled person can select a safe and effective dose without undue burden in the exercise of their routine competence.

The Court basically agrees with the EPO’s findings in T 0728/21 (Vertex), 16 November 2023, where the EPO Board held that, for a second-medical-use claim, the patent must make it credible at the filing date that the claimed composition is suitable for the therapeutic use. A deficient disclosure cannot be cured by post-published evidence. However, the credibility of a therapeutic effect may derive not only from the patent itself but also from the prior art (mn. 165, 166).

The patent need not necessarily contain clinical data. It is sufficient if it provides specific and verifiable technical information establishing a rational basis for the claimed therapeutic effect, rather than a mere unsupported assertion (mn. 168).

The Court considers, in line with the established practice before the EPO, that it is not required to exclude from the claims every possible patient population or therapeutic application for which the invention does not work. Such a requirement would, in practice, be impossible to fulfil. The Court further considers that there is no requirement in the context of sufficiency of disclosure of second medical uses, for the claims expressly to exclude all non-working patient groups (mn. 144).

Where an inventive step attack can only be built by selecting and combining multiple, e.g. more than 10, disclosures addressing different technical questions, none supplying the missing pointer, this mosaic indicates an inadmissible ex post facto analysis. The decisive question is not what the skilled person could have done, but what they would have done, starting from a realistic prior-art disclosure, at the effective date.

Although the patent-in-suit and the parent patent are closely related patents with similar subject-matter, they are legally distinct patents. Res judicata applies between the same parties on the same legal subject-matter (petitum and causa petendi). Moreover, the EPO Boards of Appeal and the UPC belong to distinct legal systems and exercise jurisdiction under different legal frameworks. An EPO decision may therefore be persuasive as to the arguments conveyed therein, but it does not bind the UPC, which must carry out its own assessment of the facts and the applicable law (mn. 225).

A party relying on a preliminary EPO opposition opinion to introduce new attacks/new prior art documents for the first time in its Rejoinder, without seeking leave to amend its case (R. 263 RoP), breaches the adversarial principle and the front-loaded character of the proceedings (Recital 5 of the Preamble to the RoP). The admission of these arguments at the Rejoinder stage would undermine procedural economy, equality of arms and the orderly conduct of the written procedure.

Deletion of dependent claims that merely simplifies the dispute, introduces no new subject-matter and raises no new validity issue for the opposing party may be admitted even at a late procedural stage, in line with equality of arms (Rules 30.2, 49.2 and 50.2 RoP).