中华人民共和国合同法（八）
Article 51 Unauthorized Disposal of Property through Contract
Where a piece of property belonging to another person was disposed of by a person without the power to do so, such contract is nevertheless valid once the person with the power to its disposal has ratified the contract, or if the person lacking the power to dispose of it when the contract was concluded has subsequently acquired such power.
第五十二条 有下列情形之一的，合同无效：
（一）一方以欺诈、胁迫的手段订立合同，损害国家利益；
（二）恶意串通，损害国家、集体或者第三人利益；
（三）以合法形式掩盖非法目的；
（四）损害社会公共利益；
（五）违反法律、行政法规的强制性规定。
Article 52 Invalidating Circumstances
A contract is invalid in any of the following circumstances:
(i) One party induced conclusion of the contract through fraud or duress, thereby harming the interests of the state;
(ii) The parties colluded in bad faith, thereby harming the interests of the state, the collective or any third party;
(iii) The parties intended to conceal an illegal purpose under the guise of a legitimate transaction;
(iv) The contract harms public interests;
(v) The contract violates a mandatory provision of any law or administrative regulation.
第五十三条 合同中的下列免责条款无效：
（一）造成对方人身伤害的；
（二）因故意或者重大过失造成对方财产损失的。
Article 53 Invalidity of Certain Exculpatory Provisions
The following exculpatory provisions in a contract are invalid:
(i) excluding one party's liability for personal injury caused to the other party;
(ii) excluding one party's liability for property loss caused to the other party by its intentional misconduct or gross negligence.
第五十四条 下列合同，当事人一方有权请求人民法院或者仲裁机构变更或者撤销：
（一）因重大误解订立的；
（二）在订立合同时显失公平的。
一方以欺诈、胁迫的手段或者乘人之危，使对方在违背真实意思的情况下订立的合同，受损害方有权请求人民法院或者仲裁机构变更或者撤销。
当事人请求变更的，人民法院或者仲裁机构不得撤销。
Article 54 Contract Subject to Amendment or Cancellation
Either of the parties may petition the People's Court or an arbitration institution for amendment or cancellation of a contract if:
(i) the contract was concluded due to a material mistake;
(ii) the contract was grossly unconscionable at the time of its conclusion.
If a party induced the other party to enter into a contract against its true intention by fraud or duress, or by taking advantage of the other party's hardship, the aggrieved party is entitled to petition the People's Court or an arbitration institution for amendment or cancellation of the contract.
Where a party petitions for amendment of the contract, the People's Court or arbitration institution may not cancel the contract instead.
第五十五条 有下列情形之一的，撤销权消灭：
(一)具有撤销权的当事人自知道或者应当知道撤销事由之日起一年内没有行使撤销权；
(二)具有撤销权的当事人知道撤销事由后明确表示或者以自己的行为放弃撤销权。
Article 55 Extinguishment of Cancellation Right
A party's cancellation right is extinguished in any of the following circumstances:
(i) It fails to exercise the cancellation right within one year, commencing on the date when the party knew or should have known the cause for the cancellation;
(ii) Upon becoming aware of the cause for cancellation, it waives the cancellation right by express statement or by conduct.