the Registrar and, on receipt of the notice, the Registrar shall rectify the Register accordingly. 19 Cancellation of registration (1) Upon a request being made in the prescribed manner by the registered proprietor of a registered layout-design, the Registrar may cancel the registration of the whole or any part of the design. (2) At any time after a layout-design has been registered, any interested person may apply to the Tribunal for the registration of the whole or any part of the design to be cancelled on the ground that¾ (a) on the effective date of its registration, the layout-design or the part concerned, as the case may be, was not capable of being registered by virtue of section seven; or (b) the registered proprietor of the layout-design or the part concerned, as the case may be, is not its proprietor as provided in section eight. and the Tribunal may make such order on the application as it thinks appropriate. (3) Notice of any application to the Tribunal in terms of subsection (2) shall be given in the prescribed manner to the Registrar and to any other person appearing from the Register to be interested in the layout-design concerned, and the Registrar and any such person shall be entitled to appear and be heard in the application. (4) Notice of any order made by the Tribunal under this section shall be served on the Registrar and, on receipt of the notice, the Registrar shall amend the Register accordingly. (5) Where the registration of the whole or any part of a layout-design is cancelled by virtue of an order under subsection (2) the design or the part concerned, as the case may be, shall be regarded as never having been registered. PART VI ASSIGNMENTS, LICENCES AND TRANSFER OF INTEREST IN REGISTERED LAOYOUT-DESIGNS 20 Right of proprietor to assign and transfer rights in registered layout-design Subject to this Part and to any rights of which notice has been entered in the Register, the proprietor of a registered layout-design may assign his title to the design, wholly or in part, or grant licences in respect of or otherwise deal with the design. 21 Assignments, etc., to be in writing Any assignment of title to a registered layout-design, and any other contract whereby the proprietorship of a registered layout-design is transferred or shared, shall have no effect unless it is in writing. 22 Registration of assignments, licences, etc. (1) Where a person becomes entitled to a registered design or to a share in a registered layout-design, whether by assignment, transmission or operation of law, he may apply to the Registrar for the registration of his title as proprietor or co­ proprietor of the design. (2) Where a person becomes entitled to an interest in a registered layout-design, whether through mortgage, licence or otherwise, which does not entitle him to the proprietorship or co-proprietorship of the design, he may apply to the Registrar for his interest to be noted in the Register. (3) If, in an application under subsection (1) or (2), the Registrar is satisfied as to the title of the person concerned, he shall¾ (a) in the case of an application under subsection (1), register the person as proprietor or co-proprietor of the layout-design concerned and enter in the Register particulars of the instrument or event by which the person derives his title; (b) in the case of an application under subsection (2), enter in the Register notice of the person’s interest, with particulars of the instrument, if any, that created it. (4) Except for the purposes of an application to rectify the Register, a document in respect of which no entry has been made in the Register under subsection (3) shall not