Labor Standards Act Article 9

(Ⅰ)Labor contracts may be divided into two categories: fixed term contracts and non-fixed term contracts. A contract in nature for temporary, short-term, seasonal or specific work may be made as a fixed term contract, but a contract for continuous work, should be a non-fixed term contract. The labor contract between a dispatching entity and a dispatched worker shall be a non-fixed term contract.(Ⅱ)In any one of the following situations, a fixed term contract shall be deemed as to be a non-fixed term upon the expiration of the contract:1. Where an employer raises no immediate objection when a worker continues his/her work.2. Where, despite the execution of a new contract, the prior contract and the new one together cover a period of more than ninety days and the period of time between expiration of the prior contract and execution of the new one does not exceed thirty days.(Ⅲ)The preceding Paragraph shall not apply in the case of a fixed term contract for specific or seasonal work.
中文原文 勞動基準法第9條
勞動契約,分為定期契約及不定期契約。
臨時性、短期性、季節性及特定性工作得為定期契約;有繼續性工作應為不定期契約。
派遣事業單位與派遣勞工訂定之勞動契約,應為不定期契約。
定期契約屆滿後,有下列情形之一,視為不定期契約:
一、勞工繼續工作而雇主不即表示反對意思者。
二、雖經另訂新約,惟其前後勞動契約之工作期間超過九十日,前後契約間斷期間未超過三十日者。
前項規定於特定性或季節性之定期工作不適用之。

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