The applicant must be given a further opportunity for interaction in Chapter II before a negative IPER is established, on condition that he has filed in due time a substantive reply to the WO-ISA in the form of amendments and/or arguments.
OJ EPO 2011, 532
Thus if, after reply to the WO-ISA, there are still objections outstanding, before issuing a negative IPER the examiner must send:
in either case generally (see GL/PCT-EPO C‑VII, 1) with a time limit to reply which is normally two months, in order to give the applicant a further opportunity to provide arguments and/or amendments in reply to any outstanding objections. Documents newly found during the top-up search (see GL/PCT-EPO C‑IV, 5) are attached to the WO-IPEA or to the telephone minutes, as appropriate.
If the applicant has not submitted any response to the WO-ISA with his demand, and the top-up search in Chapter II does not reveal any new pertinent prior art, then a negative IPER, repeating the objections raised in the WO-ISA, will be issued directly.
In the exceptional situation of a non-unitary application, where all inventions examined were found novel and inventive, but still lacking unity as the only remaining objection, a negative IPER can be sent directly without a further WO-IPEA (see GL/PCT-EPO C‑VIII, 3).