The state of the art often includes documents containing technical teachings described in general terms; these teachings in turn subsume a number of more specialised technical teachings. In assessing the novelty of subject-matter that can be subsumed under a general term in the state of the art, the question arises whether the general term makes the claimed matter fully or partially accessible to the public. In other words, it has to be established whether the general term used in the citation discloses the subject-matter defined by the special term in the claim. The prior-art disclosure needs to be identified particularly carefully in such cases. General terms of this kind occur particularly frequently in the chemical literature, which is why the relevant case law usually relates to this field. There are two types of case here:
(a) assessing the novelty of chemical substances and groups of substances in respect of general formulae (Markush formulae) under which they fall (see Chapter I.C.5.1 below), and
(b) assessing the novelty of products or processes defined by parameter ranges as against known products or processes characterised by wider or overlapping parameter ranges (see Chapter I.C.5.2 below).
These types differ mainly in technical terms, but the same principles of patent law apply to both. For this reason, the boards of appeal have always been able to adopt the same approach to questions of this nature.