Section 413A(2) in Kolkata Municipal Corporation Act, 1980
(2)Where the construction of the building has been completed by such person on or before the commencement of the Calcutta Municipal Corporation (Amendment) Act, 1996, and the document of title to land has been granted by the State Government, such person shall apply for regularization in accordance with the provisions of sub-section (1) within [three years] [Inserted by section 18 of the Calcutta Municipal Corporation (Amendment) Act, 1996 (West Bengal Act No. 6 of 1996), w.r.e.f. 4.12.1995.] from the date of commencement of the Calcutta Municipal Corporation (Amendment) Act, 1996.