Résumé de EPC2000 Art 088 pour la décision T0933/18 du 27.01.2023

T 933/18 was an appeal against the opposition division's decision to reject the opposition. The patent had been granted on a divisional application of an earlier European patent application (the parent application) filed as an international patent application. Claim 1 as granted related to a method for preparing a biosensor. Appellant I (opponent I) submitted that because the method of claim 1 was not entitled to priority contrary to the disclosure of Example 3 of the parent application, the latter anticipated the claimed method due to a "poisonous priority". It was uncontested that the disclosure of Example 2 of the priority document was identical to Examples 3 of the parent application and the patent application. Appellant I argued that G 1/15 did not apply to the present case because the glycosylation level of the GLD enzyme disclosed in Example 2 of the priority document and in Examples 3 of the parent application and the patent application was an "intrinsic" feature of GLD and not an "implicit" one. Since intrinsic features were not assessed in G 1/15, let alone their impact on the concept of a "poisonous priority", G 1/15 was irrelevant to the present case. The board disagreed for the following reasons. The case law had established that an intrinsic/inherent feature of a product normally related to a technical effect caused by an interaction with specifically selected outside conditions, i.e. a certain use of the product (see G 2/88), while structural features of a product were normally implicit to that product (see G 1/92). Example 2 of the priority document disclosed the transformation of an E. coli strain with a recombinant vector encoding a GLD gene for the production of an active GLD enzyme. It was uncontested that proteins recombinantly produced in E. coli were not glycosylated ("sugar-free", i.e. lacked any galactose, glucose, mannose and arabinose residues as referred to in claim 1), because E. coli does not contain the enzymes required for glycosylation, i.e. for adding sugar residues to a protein. This belonged to the common general knowledge of the skilled person. Furthermore, the absence or presence of sugar residues on a protein were a structural feature of this protein. A skilled person reading Example 2 of the priority application (and Examples 3 in the parent application and the patent application) therefore immediately understood that the GLD recombinantly produced in E. coli was sugar-free (i.e. not glycosylated) although this was not explicitly mentioned. The production of sugar-free GLD in E. coli was thus the clear and unambiguous consequence of the explicit disclosure of this working example in view of E. coli's generally known inability to produce glycosylated proteins. It was established case law that such a feature was implicit (see Case Law of the Boards of Appeal, 10th ed.°2022, I.C.4.3 and T 666/89). Thus, G 1/15 applied to the present case. Appellant I had contested whether claim 1 as granted belonged to the so called "AND" or "OR" claim category as defined in G 1/15. The board noted that the method in claim 1 comprised as an embodiment the use of GLD or variants thereof. These variants lacked any galactose, glucose, mannose and arabinose since the content of these sugars was defined as "10 myg or less per myg of protein", which included 0 myg/myg GLD, i.e. a "sugar-free" GLD. If, as asserted by appellant I, the disclosure of a sugar-free GLD in Example 3 of the parent application fell necessarily within the subject-matter of claim 1, then this applied likewise to the sugar-free GLD of Example 3 of the patent application too. Moreover, since both Examples 3 were identical to Example 2 of the priority document, claim 1's embodiment of a sugar-free GLD was present in the priority document too. According to the board, this finding corresponded to the practice under Art. 88 EPC established by the case law. The board concluded that the embodiment of claim 1 using a sugar-free GLD for the preparation of a biosensor had to be regarded as an "OR" claim as defined in G 1/15, since sugar-free GLD was an implicitly disclosed feature in Examples 2 and 3 of the priority document and the patent application, respectively. Consequently, this embodiment of claim 1 was entitled to partial priority. Therefore, the parent application could not anticipate the claimed method.