Deemed export refund evidence: specified acknowledgments and recipient undertakings required for supplier refund claims. Notification under rule 89(2)(g) of the West Bengal GST Rules requires suppliers of deemed export supplies to produce: (i) either an acknowledgement by the jurisdictional tax officer of the Advance Authorisation/EPCG holder confirming receipt, or a tax invoice signed by the recipient Export Oriented Unit confirming receipt; (ii) an undertaking by the recipient that no input tax credit has been availed on those supplies; and (iii) an undertaking by the recipient that they will not claim the refund and the supplier may claim it.