Supplementary duty drawback claim allows exporters to recover understated drawback payments, subject to time limits and extension conditions. A supplementary claim of Duty Drawback allows an exporter to claim additional drawback when the amount paid under section 75 is less than entitled. The claim must be filed within three months of the relevant date-publication in the Official Gazette for rates under Rules 3 or 4, communication for upward revisions under Rules 6 or 7, or payment/settlement for other cases. The three month period may be extended up to eighteen months subject to conditions and payment of the requisite fee under the Drawback Rules, 2017. Commissioners must redress zero-value claims made without proper procedure once exporters submit documents or replies.