Section 15(b) in West Bengal Value Added Tax Act, 2003
(b)on his every purchase of goods in West Bengal, after deducting therefrom-(i)purchases of goods, sales of which are declared tax-free under section 21;(ii)purchases which are shown to the satisfaction of the Commissioner to have taken place in the course of inter-state trade or commerce within the meaning of section 3 of the Central Sales Tax Act, 1956, or in the course of import of goods into, or export of the goods out of the territory of India within the meaning of section 5 of that Act;(iii)purchases of goods which are shown to the satisfaction of the Commissioner to have been made from a registered dealer in West Bengal:
