Excess anti-dumping duty determination permits refund where paid duty exceeds the actual margin of dumping after investigation. An importer may apply to the designated authority to determine the actual margin of dumping if anti-dumping duty paid appears excessive; materially deficient applications are returned for correction. On a complete application the authority investigates and, in calculating constructed export price, accounts for changes in normal value, costs between importation and resale, and subsequent selling price movements, and shall not deduct proven anti-dumping duties. If duty paid exceeds the determined margin, the authority recommends refund of the difference.