It depends: 1. The content of the contract is legal, and the signing of the contract is the true intention of both parties. Then the contract is signed by Party B and not signed by Party A, but it is valid if it is sealed by both parties or the main obligations of the contract are performed by both parties; 2. If the above conditions are not met, the contract is invalid. Article 490 of the Civil Code If the parties conclude a contract in the form of a contract, the contract is 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.

Legal objectivity:

Article 464 of the Civil Code: A contract is an agreement between civil subjects to establish, change and terminate a civil legal relationship. Agreements on status relations such as marriage, adoption and guardianship shall be governed by legal provisions on such status relations; If there are no provisions, the provisions of this part can be applied according to their nature. Article 465 of the Civil Code. Contracts established according to law are protected by law. A legally established contract is legally binding only on the parties, except as otherwise provided by law.