Patents [No. 40 of 2016 making reference to parts of the matter disclosed in the earlier application, the Registrar may direct that the fresh application be ante-dated to a date not earlier than the date on which the earlier application was lodged with the Registrar (2) A patent granted as a result of a fresh application, referred to in subsection (1), shall not be revoked or invalidated on grounds only that the invention claimed in the fresh application is not new, as specified in section fifteen, having regard to the matter disclosed in the earlier application lodged with the Registrar. 40. (1) At any time, after an application for the grant of a patent has been lodged and before it is published, the Registrar may, at the request of the applicant, made in the prescribed manner, direct that the application be post-dated or ante-dated, as the case may be. (2) The Registrar shall not direct the post-dating of an application for the grant of a patent, referred to in subsection (1), to a period exceeding six months from the date on which the application was lodged or direct the ante-dating of an application claiming priority to a date later than the date the application could have been lodged. (3) The Registrar shall not post-date an application for the grant of a patent where priority has been claimed by the applicant, in Zambia or elsewhere, or the applicant’s successor or predecessor in title, in a subsequent application which leaves any rights outstanding. 41. (1) Subject to this Act, the priority date of an invention, to which an application for the grant of a patent relates, shall be the date on which the application was first filed in the convention country. (2) Where priority is claimed in an application for a grant of a patent, as specified in subsection (1), from one or more prior applications, in a convention country or otherwise, and the invention claimed in the application is based on matter disclosed in one or more of any such prior applications, the priority date of the invention shall be the date of lodging of the earliest of such prior applications in which that matter was disclosed in so far as it is based on such earliest application. (3) An invention claimed in an application for a grant of patent may have one or more priority dates. (4) A priority date of an invention shall be the earliest priority date claimed in an application, until the contrary is proved. 817 Post-dating or ante dating of application Priority date