Section 281(4)(b) in The Bombay Provincial Municipal Corporations Act, 1949
(b)serve on every person whose name appears in the Commissioner's Assessment book as primarily liable for payment of property tax leviable under this Act, on any building included in the area to which the clearance order relates and, so far as it is reasonably practicable to ascertain such persons, on every mortgagee there of a notice stating the effect of the clearance order and that it is about to be submitted to the State Government for confirmation, and specifying the time within, and the manner in which, objections thereto can be made to the Commissioner.