Section F‑IV, 2.1, in the Guidelines for Examination in the EPO applies mutatis mutandis.[Rule 6.3(a); GL/ISPE 5.04; ]

It is not necessary that every feature should be expressed in terms of a structural limitation. Functional features are dealt with in GL/PCT‑EPO F‑IV, 6.5.

The international application must contain "one or more claims."[Art. 3(2); Art. 6; GL/ISPE 5.01; 5.02; ]

The claims must:

An ambiguity in the claims may lead to an insufficiency objection. However, ambiguity also relates to the scope of the claims, i.e. Art. 6 (see GL/PCT‑EPO F‑IV, 4). Normally, therefore, an ambiguity in a claim will lead to an objection under Art. 5 only if the whole scope of the claim is affected, in the sense that it is impossible to carry out at all the invention defined therein.

Section F‑III, 9, in the Guidelines for Examination in the EPO applies mutatis mutandis.

See ISPE Guidelines 4.25.

For the assessment of the clarity of claims referring to a trademark (Art. 6), see GL/PCT‑EPO F‑IV, 4.8.