19 C.F.R. § 351.402
(f) Reimbursement of antidumping duties and countervailing duties - (1) In general.
(i) In calculating the export price (or the constructed export price), the Secretary will deduct the amount of any antidumping duty or countervailing duty which the exporter or producer:
(ii) The Secretary will not deduct the amount of any antidumping duty or countervailing duty paid or reimbursed if the exporter or producer granted to the importer before initiation of the antidumping investigation in question a warranty of nonapplicability of antidumping duties or countervailing duties with respect to subject merchandise which was:
(2) Certificate. The importer must file prior to liquidation a certificate in the following form with the appropriate District Director of Customs:
I hereby certify that I (have) (have not) entered into any agreement or understanding for the payment or for the refunding to me, by the manufacturer, producer, seller, or exporter, of all or any part of the antidumping duties or countervailing duties assessed upon the following importations of (commodity) from (country): (List entry numbers) which have been purchased on or after (date of publication of antidumping notice suspending liquidation in the Federal Register) or purchased before (same date) but exported on or after (date of final determination of sales at less than fair value).