Deemed export refund: suppliers must produce recipient acknowledgment and undertakings to claim refund under GST law. Suppliers of deemed export supplies must produce either an acknowledgment by the jurisdictional tax officer of the Advance Authorisation or EPCG holder or a recipient-signed tax invoice confirming receipt; an undertaking from the recipient that no input tax credit has been claimed on those supplies; and an undertaking that the recipient will not claim the refund and the supplier may claim the refund.