The requirements of unity of invention and the requirements of Art. 17(2)(a)(ii) are separate requirements. However, it is possible that an application both violates the requirements of clarity, disclosure, support or conciseness to such an extent that a meaningful search cannot be carried out, and lacks unity. In that case, the examiner can combine an incomplete search and a finding of non-unity. However, the applicant should not be invited to pay additional fees for subject-matter which will later not be searched under Art. 17(2)(a)(ii). Typically, a non-unity objection could be made first and then an incomplete search applied to the searched invention. In such a case the examiner may send an informal clarification request for the first invention only and include in the invitation to pay additional fees remarks on clarity problems related to further inventions.
However, if the complexity lies in lack of clarity, the search will be restricted first, and the non-unity objection applied to the clear parts of the claimed subject-matter.