The Minister, or any other person, may, in accordance with the regulations, oppose an innovation patent that has been certified and seek the revocation of it, on one or more of the following grounds of invalidity, but on no other:
(a) that the patentee is either:
(i) not entitled to the patent; or
(ii) entitled to the patent but only in conjunction with some other person;
(b) that the complete specification does not comply with subsection 40(2), (3) or (3A);
(c) that the invention is not a patentable invention because it does not comply with paragraph 18(1A)(a), (b) or (c);
(d) that the invention is not a patentable invention under subsection 18(2) or (3).