The Equalization of Land Rights Act Article 50

If in any transfer of land ownership through sale, the one due to pay the tax fails to pay the land value increment tax liable on the land within the set time limit, the said tax may be paid by the purchaser. The land value increment tax liable on the land shall be paid by the obligee instead, if he solely declares the current transaction value of the land according to the provision of Article 47.
中文原文 平均地權條例第50條
土地所有權移轉,其應納之土地增值稅,納稅義務人未於規定期限內繳納者,得由取得所有權之人代為繳納。
依第四十七條規定由權利人單獨申報土地移轉現值者,其應納之土地增值稅,應由權利人代為繳納。

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