Refund of carry forward input tax credit: cash refunds subject to audit and blocking of claimed ITC at application. ITC accumulation from inverted duty structures, stock, capital goods, and partial reverse charge is treated differently: refunds for stock and capital goods ITC should be disallowed and carried forward; refunds for inverted duty accumulation may be granted as cash refunds only after audit and matching of input tax credits with filed purchase and sales statements. Administrative safeguards should block claimed carry forward ITC at the time of refund application via GSTN linkage, and refunds in partial reverse charge scenarios are contingent on a joint reverse charge legal mechanism.