(a) a patent for an invention (in this Chapter called the main invention ) has been applied for or granted; and
(b) the applicant or patentee (or a person authorised by the applicant or patentee) applies for a further patent for an improvement in, or modification of, the main invention; and
(c) the application for that further patent is made in accordance with the regulations;
the Commissioner may, subject to this Act and the regulations, grant a patent of addition for the improvement or modification.
(2) A patent request and complete specification relating to an application for a patent of addition must not be examined before a request is made for the examination of the patent request and complete specification relating to the application for the patent for the main invention.
(3) A patent of addition must not be granted before the patent for the main invention is granted.
(4) An appeal lies to the Federal Court against a decision of the Commissioner under this section.