(1) The examiner to whom an application for a patent is referred under section 12 shall make investigation for the purpose of ascertaining whether the invention so far as claimed in any claim of the complete specification-
(a) has been anticipated by publication before the date of filing of the applicant' s complete specification in any specification filed in pursuance of an application for a patent made in India and dated on or after the 1st day of January, 1912 ;
(b) is claimed in any claim of any other complete specification published on or after the date of filing of the applicant' s complete specification, being a specification filed in pursuance of an application for a patent made in India and dated before or claiming the priority date earlier than that date.