Patents Act, 1970
137. Multiple priorities
(1) Where two or more applications for patents in respect of inventions have been made in one or more convention countries and those inventions are so related as to constitute one invention, one application may be made by any or all of the persons referred to in sub-section (1) of section 135 within twelve months from the date on which the earlier or earliest of those applications was made, in respect of the inventions disclosed in the specifications which accompanied the basic applications.
(2) The priority date of a claim of the complete specification, being a claim based on matters disclosed in one or more of the basic applications, is the date on which that matter was first so disclosed.
(3) For the purposes of this Act, a matter shall be deemed to have been disclosed in a basic application for protection in a convention country if it was claimed or disclosed (otherwise than-by way of disclaimer or acknowledgment of a prior art) in that application, or any documents submitted by the applicant for protection in support of and at the same time as that application, but no account shall be taken of any disclosure effected by any such document unless a copy of the document is filed at the patent office with the convention application or within such period as may be prescribed after the filing of that application.