Input tax credit apportionment: credits restricted where inputs serve exempt or non business purposes and certain supplies are blocked. Input tax credit is restricted to the portion attributable to business use or to taxable (including zero rated) supplies when inputs are used partly for exempt supplies; exempt supplies include reverse charge supplies, securities, sale of land and, in specified cases, sale of building. Specific credits are blocked (including most motor vehicles, specified services such as catering and club memberships unless used for outward taxable supplies, works contract and construction on own account, composition taxed supplies, non resident receipts except imports, personal consumption, lost or gifted goods, and certain recovered taxes). Government may prescribe attribution methods and 'plant and machinery' is narrowly defined.