Section 435(1) in Kolkata Municipal Corporation Act, 1980
(1)Except as hereinafter provided in this Act, no person shall use or permit to be used any premises for any of the non residential purposes mentioned in Schedule V without or otherwise than in conformity with the terms of a municipal licence granted by the Municipal Commissioner so as not to contravene the provisions of sub-section (2):Provided that no such municipal licence shall be given in respect of any non-residential use of a premises which is otherwise than in conformity with the provisions of this Act or any other law for the time being in force or the rules or the regulations or orders made thereunder.