Input tax credit blocked for lost, stolen, destroyed or gifted goods must be reversed and added to output tax liability. Section 17(5)(h) blocks ITC for goods lost, stolen, destroyed, written off or supplied as gifts or free samples; any ITC already availed for such goods must be reversed or added to output tax. Free samples to unrelated persons are not taxable but require ITC reversal; free supplies to related persons are taxable and ITC is available; CSR free supplies are not taxable and ITC is not allowable. Inputs for customer gifts or promotional activities are not eligible for ITC.