UIN entity refund processing: centralized submission and sanctioning of inward-supply GST refunds with specified forms and verification. Entities issued a Unique Identity Number (UIN) are entitled to claim refunds of GST on inward supplies but are not treated as registered persons unless they make taxable outward supplies and therefore must obtain GSTIN. UINs are applied for via FORM GST REG-13 (with interim coordination through the Protocol Division), and refund claims must be filed quarterly in FORM RFD-10 accompanied by FORM GSTR-11 for periods where refund is claimed. Central Tax authorities will process and sanction all UIN refunds, with state nodal officers facilitating submissions and field officers verifying required certificates and compliance.