Sch. PATENTS ACT (as amended) parties alone or for regulating the manner in which it shall be proceeded with or for both those purposes, as the case may require. (7) An appeal shall lie from any decision of the Registrar under subsection (1), (2), (3), (5) or (6). 19 Prior knowledge or publication of invention excused in certain circumstances (1) A patent shall not be refused or held to be invalid by reason only of the fact that the invention in respect of which the patent is applied for or was granted or any part thereof was published, used or known prior to the effective date of the application if the applicant or the patentee, as the case may be, proves— (a) that the knowledge was acquired or the publication or use was made without his knowledge or consent; and (b) that the knowledge acquired or the matter published or used was derived or obtained from him; and (c) if he learned of the disclosure, use or knowledge before the effective date of his application for the patent, that he applied for and obtained protection for his invention with all reasonable diligence after learning of the disclosure: Provided that the protection afforded by this subsection shall not extend to an applicant for a patent or a patentee who has or whose predecessors in title have commercially worked the invention in Zimbabwe, otherwise than for the purpose of reasonable technical trial thereof, prior to the effective date of the application. (2) The exhibition at an industrial or international exhibition certified as such by the Minister of an invention or the publication subsequently of any description of the invention so exhibited by any person without the privity or consent of the inventor or the reading of a paper by the inventor before a learned society or the publication of such paper shall not prejudice the right of the inventor to apply for or obtain a patent in respect of the invention or the validity of any patent granted on the application if— (a) the application for a patent is made not later than six months from the date of the opening of the exhibition or the reading or publication of that paper, as the case may be; and (b) the inventor has, before exhibiting the invention or reading such paper or permitting such publication, given to the Registrar the prescribed notice of his intention to do so. 20 Provisions for secrecy of certain inventions (1) Where, before or after the appointed day, an application for a patent has been made in respect of an invention and it appears to the Registrar that the invention is one of a class notified to him by the competent authority as relevant for defence purposes, he may give directions for prohibiting or restricting the publication of information with respect to the invention or the communication of such information to any person or class of persons specified in the directions, and while such directions are in force the application may, subject to the directions, proceed up to the acceptance of the complete specification but the acceptance shall not be advertised nor the specification published, and no patent shall be granted in pursuance of the application. (2) Where the Registrar gives any directions in terms of subsection (1), he shall give notice of the application and of the directions to the competent authority and thereupon the following provisions shall have effect, that is to say— (a) the competent authority shall, upon receipt of such notice, consider whether the publication of the inven- tion would be prejudicial to the defence of Zimbabwe and, unless a notice under paragraph (c) has previously been given by the competent authority to the Registrar, shall reconsider that question before the expiration of nine months from the date of lodging of the application for the patent and at least once in every subsequent year; (b) for the purposes of paragraph (a), the competent authority may, at any time after the complete specification has been accepted or, with the consent of the applicant, at any time before the complete specification has been accepted, inspect the application and any documents furnished to the Registrar in connection therewith; (c) if, upon consideration of the invention, at any time it appears to the competent authority that the publication of the invention would not, or would no longer, be prejudicial to the defence of Zimbabwe, the competent authority shall give notice to the Registrar to that effect; (d) on the receipt of any notice in terms of paragraph (c), the Registrar shall revoke the directions and may, subject to such conditions, if any, as he thinks fit, extend the time for doing anything required or authorized to be done by or under this Act in connection with the application, whether or not that time has previously expired. (3) When directions have been given in terms of subsection (1), if any use of the invention is made during the continuance in force of such directions by or on behalf of or to the order of a department of the State, section thirty-four shall apply in relation to that use as if a patent had been granted for the invention. (4) If an applicant for a patent has suffered loss or damage by reason of his invention having been kept secret in pursuance of directions in terms of subsection (1), the Minister, with the consent of the Minister responsible for finance, shall pay to him such reasonable compensation as is agreed upon or, in default of agreement, as may be determined by the Tribunal on a reference under subsection (1) of section thirty-six. (5) Where a patent is granted in pursuance of an application in respect of which directions have been given in terms of subsection (1), no renewal fees shall be payable in respect of any period during which those directions were in force. (6) If any person fails to comply with any direction given under this section he shall be guilty of an offence and liable to a fine not exceeding level seven or to imprisonment for a period not exceeding two years or to both such fine and such imprisonment. 8 (7) In this section— “competent authority” means the Minister responsible for defence or any other Minister whom the President, by statutory instrument, designates as being the competent authority for the purposes of this section. PART IV GRANT, EFFECT AND TERM OF P ATENT 21 Grant and sealing of patent (1)* Subject to the provisions of this Act relating to opposition and to any other power of the Registrar to refuse the grant, a patent sealed with the seal of the Patent Office shall, if the prescribed request is made within the time allowed under this section, be granted to the applicant or applicants within that time or as soon as may be thereafter,