Administrative Regulations on Radio Waves Article 6

Under the premise of not causing harmful interference, the competent authority may assign the same radio frequency to more than one user.
中文原文 電波監理業務管理辦法第6條
同一無線電頻率,在不發生妨害性干擾原則下,主管機關得指配予一個以上之使用者。

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