CENVAT credit utilisation requirement restricts exemption refunds and permits account current credit option under specified procedural conditions. Amendments require prior utilisation of the entire CENVAT credit balance when all goods of a manufacturer are exempt, limit refunds where some goods are non exempt to duty paid less attributable CENVAT credit, and allow an optional account current credit mechanism treating such credited duty as cash payment. The option must be exercised in writing at the start of a financial year, monthly statements and filing deadlines apply, the Commissioner will verify and determine refundable amounts, excess credits must be reversed promptly, and irregular credits are recoverable as erroneously refunded duty.