2.1. Form of claims: Rule 43(1) EPC

Rule 43(1)(a) and (b) EPC (like R. 29(1)(a) and (b) EPC 1973) define the two-part form which a claim must contain where appropriate: (a) a statement indicating the designation of the subject-matter of the invention and those technical features which are necessary for the definition of the claimed subject-matter but which, in combination, form part of the prior art ("preamble"), and (b) a characterising portion specifying the technical features for which, in combination with the features stated in the first part, protection is sought. See also EPC Guidelines F‑IV, 2 – April 2025 version.