R. 63(3) EPC is based on the same reasoning as former R. 62a(2) EPC. It states that when a partial search report has been drawn up, the examining division shall invite the applicant to restrict the claims to the subject-matter searched unless it finds that the objection under paragraph 1 was not justified.
R. 63(3) EPC in conjunction with proposed R. 137(5), second sentence, EPC, ensures that no patent will be granted with claims directed to unsearched subject-matter. Whereas proposed R. 137(5), second sentence, EPC, relates to amendments made during the grant procedure which are under the control of the examining division, R. 63(3) EPC is necessary to avoid originally filed claims relating to the unsearched subject-matter remaining in the application. If the applicant does not comply with the invitation under R. 63(3) EPC, the application will not meet all requirements of the EPC and may be refused under Art. 97(2) EPC (CA/29/09, point 7 and 15).