2.2. The rules of interpretation of the Vienna Convention

It is established in the jurisprudence that the rules of interpretation provided for in Art. 31 and 32 Vienna Convention are to be applied when interpreting the EPC. These principles have been acknowledged and applied by the Enlarged Board and the boards of appeal alike (G 5/83; G 2/02 and G 3/02; G 2/08 date: 2010-02-19, OJ 2010, 456; G 2/12; G 2/13; G 3/14, OJ 2015, A102; G 1/16, OJ 2018, A70; G 1/18, OJ 2020, A26; G 3/19, OJ 2020, A11; J 10/98, OJ 2003, 184; T 128/82, OJ 1984, 164; T 1173/97, OJ 1999, 609; T 1807/15, OJ 2021, A92; J 12/18; J 7/21; T 695/18). In G 2/08 date: 2010-02-19 the Enlarged Board stated that from the reading of Art. 31 and 32 Vienna Convention taken together it follows that the provisions of a treaty (here the EPC) must first be construed according to the ordinary meaning of the terms in their context and in the light of its object and purpose, which means that the judge is not entitled to depart from clear provisions of law, this principle pertaining to the requirement of good faith. From the wording of Art. 32 Vienna Convention it can also be derived that preparatory documents are primarily to be drawn into consideration in order to confirm a meaning or to determine a meaning if the first and ordinary means of construction would lead to ambiguity or to an absurd result (see also decision G 1/07 of 15 February 2010 date: 2010-02-15, OJ 2011, 134, point 3.1 of the Reasons; G 1/18, point III. of the Reasons).

According to the Enlarged Board in G 2/12 and G 2/13 (OJ 2016, A27 and OJ 2016, A28) this objective method of interpretation is directed to establishing the "authentic" meaning of the relevant provision and its legal terms. The starting point of interpretation is thus the wording, i.e. the "objective" meaning, regardless of the original "subjective" intention of the contracting parties. To this end, the provisions are to be read in their context so that they comply with the object and purpose of the EPC.