The EPO acting as ISA accepts international applications drawn up in Dutch if the application was filed with the Netherlands patent office as RO.
Therefore, for such files, a translation is not required for the purpose of the international search by the EPO as ISA. However, under Rule 12.4(a), within 14 months of the priority date, a translation must be filed with the RO in a language of publication accepted by the RO for the purpose of international publication, i.e. English, French or German in the case of the Netherlands patent office as RO. The EPO as ISA will establish the ISR and WO‑ISA in that language if it is already known at the time of carrying out the international search; otherwise they will be in the language of the request form, i.e. English, French or German. See also PCT Applicant's Guide, International Phase, Annex C, NL.