Income Tax Act Article 9

The terms "income from the transaction of property" and "losses from the transaction of property" as used in this Act refer to profits and losses resulting from sale, purchase, or exchange of property by a taxpayer who comes to possess the property through a manner other than engaging in regular sales and purchases of such properties for profit-seeking purposes.
中文原文 所得稅法第9條
本法稱財產交易所得及財產交易損失,係指納稅義務人並非為經常買進、賣出之營利活動而持有之各種財產,因買賣或交換而發生之增益或損失。

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