The author points out that modification right, in its nature, is right in formation, and it challenges the correctness of the definition of contract in the theory of contract law in civil system.

有人认为由它的行使所体现的效力只是情势变更原则的第一次效力；笔者认为该变更权在性质上属于形成权，它的出现对大陆法系合同法理论中的合同定义的正确性提出了挑战。

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