Code of Civil Procedure Article 446
No amendment or addition of claims may be made without the opposing party's consent, except in the cases provided in the second to the sixth subparagraphs inclusive of the first paragraph of Article 255.No counterclaim may be raised without the opposing party's consent except in case of any of the following:1. Where the existence or nonexistence of a certain legal relation, based upon which relation the principal action should be decided, becomes disputed and the new counterclaim seeks to confirm such legal relation;2. Where the claimant has interests in raising a counterclaim from the same subject matter of the original claim;3. Where the claimant has interests in raising a counterclaim with respect to the balance as a result of a setoff raised.
中文原文 民事訴訟法第446條
訴之變更或追加，非經他造同意，不得為之。
但第二百五十五條第一項第二款至第六款情形，不在此限。
提起反訴，非經他造同意，不得為之。
但有下列各款情形之一者，不在此限：
一、於某法律關係之成立與否有爭執，而本訴裁判應以該法律關係為據，並請求確定其關係者。
二、就同一訴訟標的有提起反訴之利益者。
三、就主張抵銷之請求尚有餘額部分，有提起反訴之利益者。
但第二百五十五條第一項第二款至第六款情形，不在此限。
提起反訴，非經他造同意，不得為之。
但有下列各款情形之一者，不在此限：
一、於某法律關係之成立與否有爭執，而本訴裁判應以該法律關係為據，並請求確定其關係者。
二、就同一訴訟標的有提起反訴之利益者。
三、就主張抵銷之請求尚有餘額部分，有提起反訴之利益者。