Enforcement Rules of the Patent Act Article 62

Where priority is claimed pursuant to Paragraph 1, Article 28 or Paragraph 1, Article 30 of the Act, the so-called “prior to the filing of application” in Subparagraph 3, Paragraph 1, Article 59 and Paragraph 1, Article 99 of the Act shall mean prior to the priority date.
中文原文 專利法施行細則第62條
本法第五十九條第一項第三款、第九十九條第一項所定申請前,於依本法第二十八條第一項或第三十條第一項規定主張優先權者,指該優先權日前。

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