Input tax credit claim form GST ITC-01 requires stock, invoice details and tax-wise ITC allocation. Form GST ITC-01 facilitates claims of input tax credit under section 18(1)(a)-(d) by capturing GSTIN and name details, the relevant date tied to the claim route, and detailed tabulations of inputs, inputs in semi finished/finished goods, and capital goods with invoice/bill of entry data, quantities, values and ITC claimed by tax head. It permits FIFO where invoices are not identifiable and prescribes a quarterly five percentage point reduction in capital goods value for ITC calculation, certification by a Chartered/Cost Accountant where required, and a signed verification declaration.