56. Validity of patents of addition
(1) The grant of a patent of addition shall not be refused, and a patent granted as one shall not be revoked or invalidated, on the ground only that the invention claimed does not involve an inventive step having regard to publication or use of (a) the main invention, or (b) any improvement/modification described in the specification of a patent of addition to the main patent or an application for such a patent of addition; and the validity of a patent of addition shall not be questioned on the ground that the invention ought to have been the subject of an independent patent.
(2) For removal of doubts, in determining the novelty of the invention claimed in a complete specification for a patent of addition, regard shall also be had to the complete specification in which the main invention is described.
