1. General remarks 

The objective of the international preliminary examination is to formulate a preliminary and non-binding opinion on the questions whether the claimed invention appears to be novel, to involve an inventive step and to be industrially applicable.

The PCT does not define what is meant by "invention", but Rules 39 and 67 contain a list of subject-matter for which the ISA or IPEA is not required to carry out an international search or an international preliminary examination, respectively (see also GL/PCT‑EPO B‑VIII, 2). The Agreement between the EPO and WIPO in relation to the functioning of the EPO as an International Authority under the PCT indicates the subject-matter which the EPO is not required to search or examine, and according to its Art. 4 and Annex C the discretion not to search or examine is exercised by the EPO as ISA and IPEA only to the extent that such subject-matter is not searched under the provisions of the EPC, specifically Art. 52(2) EPC, Art. 52(3) EPC, Art. 53(b) EPC and Art. 53(c) EPC.