PCT International Search and Preliminary Examination Guidelines
17.01 This chapter covers the content of any written opinion, whether established by the International Searching Authority or the International Preliminary Examining Authority. It also covers the content of the international preliminary examination report, which follows a very similar format to a written opinion.
17.02 The purpose of a written opinion, issued by the International Searching Authority or the International Preliminary Examining Authority, is to give a primary indication to the applicant of the defects which the examiner considers to exist in the application so that the applicant can determine the most appropriate course of action, including the possibilities of filing a demand for international preliminary examination or submitting comments or amendments, before any international preliminary examination report is drawn up. Its primary role is to identify whether or not the claimed invention appears to be novel, involve an inventive step (be non-obvious) and be industrially applicable. It will also include opinions on certain other substantive defects in so far as checked by the Authority, mainly where these affect the ability to determine the novelty, inventive step or industrial application of the invention accurately, and on certain defects in the form of the international application (see Rule 43bis.1(a) and Rule 66.2(a)).
17.03 The international preliminary examination report follows the same format as a written opinion and, assuming that international preliminary examination is demanded, is established taking into account any amendments or observations filed in response to the written opinions (either of the International Searching Authority or of the International Preliminary Examining Authority) which precede it.