Patents Act, 1970
56. Validity of patents of addition
(1) The grant of a patent of addition shall
not be refused, and a patent granted as a patent of addition shall not be
revoked or invalidated, on the ground only that the invention claimed in the
complete specification does not involve any inventive step having regard to any
publication or use of-
(a) the main invention described in the
complete specification relating thereto; or
(b) any improvement in or modification of the
main invention described in the complete specification of a patent of addition
to the patent for the main invention or of 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 the removal of doubts it is hereby declared that in
determining the novelty of the invention claimed in the complete specification
filed in pursuance of an application for a patent of addition regard shall be
had also to the complete specification in which the main invention is
described.