82ter.1

a) If the applicant proves to the satisfaction of any designated or elected Office that the international filing date is incorrect due to an error made by the receiving Office or that the priority claim has been erroneously considered void by the receiving Office or the International Bureau, and if the error is an error such that, had it been made by the designated or elected Office itself, that Office would rectify it under the national law or national practice, the said Office shall rectify the error and shall treat the international application as if it had been accorded the rectified international filing date or as if the priority claim had not been considered void.
b) Where the international filing date has been accorded by the receiving Office under Rule 20.3b)(ii) or 20.5d) on the basis of the incorporation by reference under Rules 4.18 and 20.6 of an element or part but the designated or elected Office finds that:

(i) the applicant has not complied with Rule 17.1a), b) or (b-bis) in relation to the priority document;
(ii) a requirement under Rule 4.18, 20.6a)(i) or 51bis.1e)(ii) has not been complied with; or
(iii) the element or part is not completely contained in the priority document concerned;
 the designated or elected Office may, subject to paragraph c), treat the international application as if the international filing date had been accorded under Rule 20.3b)(i) or 20.5b), or corrected under Rule 20.5c), as applicable, provided that Rule 17.1c) shall apply mutatis mutandis.
c) The designated or elected Office shall not treat the international application under paragraph b) as if the international filing date had been accorded under Rule 20.3b)(i) or 20.5b), or corrected under Rule 20.5c), without giving the applicant the opportunity to make observations on the intended treatment, or to make a request under paragraph d), within a time limit which shall be reasonable under the circumstances.
d) Where the designated or elected Office, in accordance with paragraph c), has notified the applicant that it intends to treat the international application as if the international filing date had been corrected under Rule 20.5c), the applicant may, in a notice submitted to that Office within the time limit referred to in paragraph c), request that the missing part concerned be disregarded for the purposes of national processing before that Office, in which case that part shall be considered not to have been furnished and that Office shall not treat the international application as if the international filing date had been corrected.