What are the circumstances of the contract is invalid

Legal analysis: the contract is invalid in the following circumstances:

(a) a party to fraud, coercion, to the detriment of national interests:

(b) malicious collusion, to the detriment of the state, the collective or the interests of a third party;

(c) in a lawful form to cover up an illegal purpose;

(d) damage to the interests of the public social ****.

(v) violating the mandatory provisions of laws and administrative regulations.

Legal basis: the Chinese people's *** and National Code Article 153 Violation of mandatory provisions of laws and administrative regulations of civil legal acts are invalid. However, the mandatory provisions do not lead to the invalidity of the civil legal act except. Violation of public order and morals of the civil legal act is invalid.

Article 154 A civil legal act in which the perpetrator colludes in bad faith with the opposite party to the detriment of the lawful rights and interests of others is null and void.

Article 148 If a party uses fraudulent means to make the other party commit a civil legal act in violation of its true meaning, the defrauded party shall have the right to request the people's court or arbitration institution to revoke it.