Patent Attorney Act Article 15
A non-citizen who practices as a patent attorney in the Republic of China shall present all statements to the Competent Authority in the official language of the Republic of China; the documents presented shall mainly be in the official language of the Republic of China.
中文原文 專利師法第15條
外國人在我國執行專利師業務者，於向有關機關陳述時，應用我國語言；所陳文件，應以我國文字為主。