Under Art. 123(2), it is impermissible to add to a European application subject-matter which the skilled person cannot derive directly and unambiguously, using common general knowledge and also taking into account any features implicit to a person skilled in the art in what is expressly mentioned in the document, from the disclosure of the application as filed. Literal support is, however, not required by the wording of Art. 123(2) (see T 667/08).
The term "implicit disclosure" means no more than the clear and unambiguous consequence of what is explicitly mentioned in the application as filed. Thus, the common general knowledge must be taken into account in deciding what is clearly and unambiguously implied by the explicit disclosure of a document. However, the question of what may be rendered obvious by that disclosure in the light of common general knowledge is not relevant to the assessment of what is implicitly disclosed by that document (T 823/96, T 1125/07).
When assessing the conformity of the amended claims with the requirements of Art. 123(2), the focus is placed on what is really disclosed to the skilled person by the documents as filed as directed to a technical audience. In particular, the examining division needs to avoid disproportionally focusing on the structure of the claims as filed to the detriment of the subject-matter that the skilled person would directly and unambiguously derive from the application as a whole.
Furthermore, the assessment of the requirements of Art. 123(2) is made from the standpoint of the skilled person on a technical and reasonable basis, avoiding artificial and semantic constructions (T 99/13).
Source: http://www.epo.org/law-practice/legal-texts/html/guidelines/e/h_iv_2_2.htm
Date retrieved: 17 May 2021