If the parties conclude a contract in the form of a contract, the contract shall be established when both parties sign or seal it. The contract is valid as long as the signatures of both parties are true and the contents of the contract do not violate the mandatory provisions of laws and administrative regulations, public order and good customs. It should be noted that the signature is invalid if the parties have a special agreement or the law stipulates that it must be sealed.

According to the nature of the signature, it can be divided into legal person signature and natural person signature:

1. Signature of legal person: Generally, official documents are only stamped with the legal person seal (official seal) at the unit name at the end of the official document; Some official documents involving the responsibility of the legal representative must have the name and official seal of the unit, as well as the signature and private seal of the legal representative.

2. Signature of natural person: handwritten signature in the file name column, and personal seal of the party concerned.

To sum up: before signing, stamping or fingerprinting, one party has fulfilled its main obligations and the contract is established when the other party accepts it. Therefore, under normal circumstances, only the parties agree to stamp can they sign.

Legal basis:

People's Republic of China (PRC) Civil Code

Article 490

If the parties enter into a contract in the form of a contract, the contract shall be established when the parties sign, seal or press their fingerprints. Before signing, sealing or fingerprinting, one party has fulfilled its main obligations, and the contract is established when the other party accepts it.

A contract shall be concluded in written form as stipulated by laws, administrative regulations or agreed by the parties. If the parties do not do this in writing, but one party has fulfilled its main obligations and the other party accepts it, the contract is established.