3.4 Supplementary International Search (SIS)
3.4.1.General
3.4.001In its capacity as Authority specified for supplementary search, hereafter referred to as the Supplementary International Searching Authority or SISA, the EPO will carry out a supplementary international search (SIS) at the applicant's request, except for applications where it has already acted as ISA.
R. 45bis PCT
Agreement EPO-WIPO, Annex B
OJ 2017, A115
OJ 2018, A24
OJ 2020, A35
OJ 2022, A37
WIPO PCT Guide 8.001-8.053
PCT Newsletter 4/2011, 9
1/2012, 10
9/2016, 8
3.4.002The purpose of the SIS is to provide the applicant with a supplementary international search report (SISR) in addition to the search carried out under Article 15 PCT by the competent ISA ("main search") (see point 3.2.005). In particular, in view of the growing linguistic diversity of the prior art and considering the language knowledge available in the EPO, a SISR established by the EPO can be very useful to applicants.
3.4.003Since the SISR is established within 28 months from the priority date, it may improve the basis for deciding on national phase entry and, in particular where a SISR is drawn up by the EPO, on whether or not to enter the European phase. The SIS reduces the risk of an applicant being faced with relevant prior art only after incurring considerable expenditure for entry into the national/regional phase.
3.4.004In the procedure before the EPO as SISA, no separate written opinion is established. However, the EPO will provide explanations in an annex to the SISR ("Scope Annex") which are equivalent to the information contained in a written opinion established by the EPO as ISA (WO‑ISA) (see point 3.2.007).
3.4.005If the EPO has acted as SISA and established a SISR, in principle, no supplementary European search report will be drawn up in the European phase. Further, the applicant will be invited in a communication under Rule 161 EPC to correct any deficiencies set out in the Scope Annex to the SISR upon entry into the European phase (see point 5.4.025).