Regulations Governing the Offsetting or Refund of Duties and Taxes on Raw Materials for Export Products Article 6

The customs duties and commodity tax which may be offset or refunded on imported raw materials for export products shall be assessed based on the duty rate applicable at the time of import. However, in the case of imported raw materials which are assessed based on the rate in the Third Column of the Customs Import Tariff, the customs duties and commodity tax which may be offset or refunded for export products shall be assessed based on the rate in the First Column of the Customs Import Tariff.
中文原文 外銷品沖退原料稅辦法第6條
外銷品進口原料所得沖退之關稅及貨物稅,依其進口時適用之關稅稅率核計。
但進口時適用海關進口稅則第三欄稅率者,應依第一欄稅率核計沖退關稅及貨物稅。

English translation for reference only; the Chinese text prevails. Not legal advice.