Legal analysis: Apply for identification, such as identification of stamps or signatures. Conditions for proving the validity of a contract:

1. The actor has the corresponding capacity for civil conduct;

2. The intention is true;

3. It does not violate the law or Social welfare interests. Because the above three conditions are general criteria for legality of civil acts, they should of course also apply to civil acts such as parties signing contracts.

Legal basis: Article 148 of the "People's Liberation Army and Civil Code of the People's Republic of China" If one party uses fraudulent means to cause the other party to perform a civil legal act contrary to its true intention, the party affected by the fraud shall Have the right to request the people's court or arbitration institution to revoke it.