2.2 Division's approach 

Lack of unity is not a ground for revocation in later proceedings. Therefore, although an objection should certainly be raised in sufficiently clear cases and an amendment requested, the division should not base an objection on an interpretation that is overly rigid, narrow, literal or academic. This is particularly so during search when the possible lack of unity does not necessitate a further search. That is, the search division may raise a lack of unity objection at the search stage but will not invite the applicant to pay further search fees for other inventions that can be searched without effort together with the first invention, see F‑V, 4.

If a lack of unity is established, the claimed subject-matter is divided into separate inventions and/or inventions grouped together in view of their technical relationships (see F‑V, 3.2), i.e. according to any common matter comprising same or corresponding potential special technical features. In this context, an invention must have technical character and be concerned with a technical problem within the meaning of Art. 52(1) (see G‑I, 1) but it does not necessarily need to meet other requirements for patentability, such as novelty and inventive step (see G‑VI and G‑VII).

Lack of unity may be evident a priori, i.e. before carrying out a prior-art search, or may become apparent a posteriori, i.e. after taking into account the prior art revealed by the search in terms of novelty and inventive step.