When in a supplementary European search following an international (PCT) search a problem of unity of invention arises, a partial supplementary European search report is drawn up on the invention or group of inventions first mentioned in the claims (see F‑V, 3.4) serving as basis for the supplementary European search (Rule 164(1)(a)), independently of the findings of the International Searching Authority as regards unity of invention. Together with this partial search report, the applicant receives an invitation to pay further search fees for each invention other than the one first mentioned in the claims (Rule 164(1)(b)), i.e. the same procedure is followed as for the non-unity invitation for EP direct applications under Rule 64(1) (see B‑VII, 1.2). A provisional opinion on the patentability of the invention or unitary group of inventions first mentioned in the claims and the reasons for non-unity findings will also be provided.[Art. 153(7); Rule 164(1); ]