Fundamental Communications Act Article 9

Communications enterprises shall publicly disclose necessary information with respect to consumption and shall provide fair and reasonable services to protect the rights and interests of consumers.
中文原文 通訊傳播基本法第9條
通訊傳播事業對於消費之必要資訊應予公開並提供公平合理之服務,以保障消費者權益。

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