Commodity Tax Act Article 17

In case where the competent tax authority, finds that the selling prices and taxable value reported by the manufacturer are not in compliance with Articles 13 to 16, through its investigating process, the competent tax authority shall adjusted the taxable value based on the investigation results or the standards established by the MOF in consultation with the related competent authority.The standards stated in the preceding paragraph are to be established in all districts by referring to the actual manufactured domestically condition in the market by the MOF in consultation with the related competent authority.
中文原文 貨物稅條例第17條
產製廠商申報應稅貨物之銷售價格及完稅價格,主管稽徵機關發現有不合第十三條至第十六條之疑慮時,始得進行調查,並應依查得資料或財政部會商有關機關訂定之標準調整其完稅價格。
前項標準,由財政部會商有關機關參照貨物出廠時之實際市場情形定之。

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