Patents Act, 1964

Patents of addition.

28.—(1) Subject to the provisions of this section, where application is made for a patent in respect of any improvement in or modification of an invention (in this Act referred to as the main invention) and the applicant also applies or has applied for a patent for that invention or is the patentee in respect thereof, the Controller may, if the applicant so requests, grant the patent for the improvement or modification as a patent of addition.

(2) Subject to the provisions of this section, where an invention, being an improvement in or modification of another invention, is the subject of an independent patent and the patentee in respect of that patent is also the patentee in respect of the patent for the main invention the Controller may, if the patentee so requests, by order revoke the patent for the improvement or modification and grant to the patentee a patent of addition in respect thereof, bearing the same date as the date of the patent so revoked.

(3) A patent shall not be granted as a patent of addition unless the date of filing of the complete specification was the same as or later than the date of filing of the complete specification in respect of the main invention.

(4) A patent of addition shall not be sealed before the sealing of the patent for the main invention; and if the period within which, but for this provision, a request for the sealing of a patent of addition could be made under section 23 of this Act expires before the period within which a request for the sealing of the patent for the main invention may be so made, the request for the sealing of the patent of addition may be made at any time within the last-mentioned period.

(5) A patent of addition shall be granted for a term equal to that of the patent for the main invention, or so much thereof as is unexpired, and shall remain in force during that term or until the previous cesser of the patent for the main invention and no longer:

Provided that—

(a) if the term of the patent for the main invention is extended under the last foregoing section of this Act, the term of the patent of addition may also be extended accordingly; and

(b) if the patent for the main invention is revoked under this Act, the Court or Controller, as the case may be, may order that the patent of addition shall become an independent patent for the remainder of the term of the patent for the main invention, and thereupon the patent shall continue in force as an independent patent accordingly.

(6) No renewal fees shall be payable in respect of a patent of addition; but, if any such patent becomes an independent patent by virtue of an order under the last foregoing subsection, the same fees shall thereafter be payable, upon the same dates, as if the patent had been originally granted as an independent patent.

(7) An appeal shall lie from any decision of the Controller under this section.