The Communication Security and Surveillance Act Article 4

Persons under surveillance as defined in this Act include, in addition to those delineated in the provisions of Article 5 and Article 7, those who assist in sending, transmitting, receiving communications or those who provide communication equipment, or facilities.
中文原文 通訊保障及監察法第4條
本法所稱受監察人,除第五條及第七條所規定者外,並包括為其發送、傳達、收受通訊或提供通訊器材、處所之人。

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