(1) A design may be registered in respect of any or all of the articles comprised in a prescribed class of articles.
     (2) Any question arising as to the class within which any article falls shall be determined by the Controller whose decision in the matter shall be final.
     (3) Where a design has been registered in respect of any article comprised in a class of article, the application of the proprietor of the design to register it in respect of some one or more other articles comprised in that class of articles shall not be refused, nor shall the registration thereof invalidated--
         (a) on the ground of the design not being a new or original design, by reason only that it was so previously registered; or
         (b) on the ground of the design having been previously published in India or in any other country, by reason only that it has been applied to article in respect of which it was previously registered:
     Provided that such subsequent registration shall not extend the period of copyright in the design beyond that arising from previous registration.
     (4) Where any person makes an application for the registration of a design in respect of any article and either--
         (a) that design has been previously registered by another person in respect of some other article; or
         (b) the design to which the application relates consists of a design previously registered by another person in respect of the same or some other article with modifications or variations not sufficient to alter the character or substantially to affect the identity thereof,
then, if at any time while the application is pending the applicant becomes the registered proprietor of the design previously registered, the foregoing provisions of this section shall apply as if at the time of making the application, the applicant, had been the registered proprietor of that design.