Section 16A(4) in The West Bengal Public Libraries Act, 1979
(4)Any library, not being a public library, registered or deemed to have been registered under the West Bengal Societies Registration Act, 1961, or any library, not being a public library, established or managed by any society or association of individuals, registered or deemed to have been registered under that Act shall, on being declared to be a sponsored public library, cease to be a library registered or deemed to have been registered under that Act or a library established or managed by such society or association of individuals and thereupon the provisions of this Act and the rules made thereunder shall apply to such library.