Company Act Article 167-3

A company which buys back its shares and assigns or transfers those shares to its employees in accordance with Article 167-1 or other laws may restrain such shares from being assigned or transferred to others within a specific period of time which shall in no case be longer than two years.
中文原文 公司法第167-3條
公司依第一百六十七條之一或其他法律規定收買自己之股份轉讓於員工者,得限制員工在一定期間內不得轉讓。
但其期間最長不得超過二年。

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