Refund of tax: claims subject to limitation, documentation, provisional payment for export-related claims and withholding safeguards. Claims for refund require an application to the proper officer within the limitation period from the relevant date, accompanied by prescribed documentary evidence or, for smaller claims, a declaratory substitute; the proper officer must determine refundable amounts and issue an order within a prescribed time. Refunds of unutilized input tax credit are limited to exports or where input tax rates exceed output tax rates, with exclusions for exports subject to export duty. Revenue-protective measures allow withholding or deduction of refunds where returns or tax liabilities are outstanding or where appeals may adversely affect revenue, subject to hearing and interest where appropriate.