Zusammenfassung von EPC2000 Art 056 für die Entscheidung T1994/22 vom 15.04.2024

See also abstract under Article 56 EPC regarding the purported technical effect of improved photostability. In T 1994/22 the appeal lay from the opposition division's decision to reject the oppositions filed against the European patent. Claim 1 of the main request related to Form II of selexipag, an agonist of the prostaglandin receptor PGI2. The appellant (opponent) objected to the inventive step of the subject-matter of claim 1 of the main request in view of D10 as the closest prior art. The distinguishing feature of claim 1 of the main request in view of example 84 of D10 was the crystalline form, namely Form II of selexipag. In view of the available experimental results, the board concluded that Form II exhibited the best stability but only intermediate industrial processability, intermediate residual solvent content and an intermediate amount of residual impurities. Contrary to the situation in T 672/21 there was no balance of beneficial properties for Form II according to the main request. The objective technical problem could therefore only be considered that of providing a crystalline form of selexipag which is the best for one property, but only intermediate for all other tested properties. The respondent submitted that, in line with T 1684/16, there was no reasonable expectation based on the prior art that a suggested investigation in terms of polymorph screening would be successful in finding a form of selexipag having a balance of beneficial properties in terms of stability, industrial processability, solvent content and purity. The board disagreed. Based on T 1684/16 and in line with T 777/08, an inventive step can be acknowledged if the claimed polymorph has an unexpected property meaning that its selection is non-arbitrary. In the present case, the board saw nothing unexpected in finding a polymorph that was optimum for one property but only intermediate for several other properties. If this were unexpected and thus gave rise to an inventive step being acknowledged, an applicant or proprietor having identified a new polymorph would simply need to carry out tests for long enough to find one single property for which the identified polymorph performed best. This might result in a situation in which almost any polymorph in the world becomes inventive, which would render Art. 56 EPC meaningless. Therefore, the selection of Form II is an arbitrary selection from the host of alternatives covered by the closest prior art. Such an arbitrary selection without any unexpected balance of properties being produced cannot contribute to inventive step. The subject-matter of claim 1 of the main request therefore does not involve an inventive step in view of D10 as the closest prior art.