Labor Standards Act Article 19

Upon termination of a labor contract, neither an employer nor the employer's agent shall reject a request from the worker for proof of service record.
中文原文 勞動基準法第19條
勞動契約終止時,勞工如請求發給服務證明書,雇主或其代理人不得拒絕。

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