Section 71(1)(c) in Kolkata Municipal Corporation Building Rules, 2009
(c)if such transfer takes place at any time after completion of such erection or such addition or alteration-(i)the completion certificate if not already granted, shall not be granted, and(ii)such portion of the building or the addition or alteration as is not allowable under these rules because of such transfer, shall be demolished, and(iii)the extent of the building or such addition or alteration and the portion there which shall be demolished, shall be determined by the Municipal Commissioner: