Enforcement Rules of the Government Procurement Act Article 72

Where a price reduction or a price reduction with comparison is conducted pursuant to paragraph 1 of Article 53 or Article 54 of the Act, the tenderers participate therein shall provide their revised tender prices in writing.Where there is only one tenderer meeting the requirements of the tender documentation or it is a procurement of single tendering, and where price reduction is requested since the tender price exceeds the government estimate or an amount recommended by a committee, the entity shall accept the outcome as to the tenderer reduces in writing its tender price either to the government estimate or the amount recommended or to a certain amount less than the government estimate or the amount recommended. The same shall also apply to the entity where there remains only one tenderer reducing in writing its tender price at a price reduction and comparison procedure.
中文原文 政府採購法施行細則第72條
機關依本法第五十三條第一項及第五十四條規定辦理減價及比減價格,參與之廠商應書明減價後之標價。
合於招標文件規定之投標廠商僅有一家或採議價方式辦理採購,廠商標價超過底價或評審委員會建議之金額,經洽減結果,廠商書面表示減至底價或評審委員會建議之金額,或照底價或評審委員會建議之金額再減若干數額者,機關應予接受。
比減價格時,僅餘一家廠商書面表示減價者,亦同。

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