State tax exemption on intra state supplies targets margin based taxation for specified used motor vehicle categories, excluding credit availed suppliers. Exemption of State tax is granted on specified intra state supplies of old and used motor vehicles by exempting tax in excess of an amount calculated on the supplier's margin at prescribed rates for each vehicle category; the margin is defined as consideration minus depreciated value for depreciating suppliers or as selling price minus purchase price otherwise, with negative margins ignored, and the exemption does not apply where the supplier has availed input tax or related tax credits.