Patents Act, 1970
9. Provisional and complete specifications
(1) Where an application for a patent (not being a convention application) is accompanied by a provisional specification, a complete specification shall be filed within twelve months from the date of filing of the application, and if the complete specification is not so filed the application shall be deemed to be abandoned:
PROVIDED that the complete specification may be filed at any time after twelve months but within fifteen months from the date aforesaid, if a request to that effect is made to the Controller and the prescribed fee is paid on or before the date on which the complete specification is filed.
(2) Where two or more applications in the name of the same applicant are accompanied by provisional specifications in respect of inventions which are cognate or of which one is a modification of another and the Controller is of opinion that the whole of such inventions are such as to constitute a single invention and may properly be included in one patent, he may allow one complete specification to be filed in respect of all such provisional specifications.
(3) Where an application for a patent (not being a convention application) is accompanied by a specification purporting to be a complete specification, the Controller may, if the applicant so requests at any time before the acceptance of the specification, direct that such specification shall be treated for the purposes of this Act as a provisional specification and proceed with the application accordingly.
(4) Where a complete specification has been filed in pursuance of an application for a patent accompanied by a provisional specification or by a specification treated by virtue of a direction under sub-section (3) as a provisional specification, the Controller may, if the applicant so requests at any time before the acceptance of the complete specification, cancel the provisional specification and post-date the application to the date of filing of the complete specification.