Legal analysis: In practice, only signing, or only stamping and fingerprinting are valid. The parties may also stipulate in the contract that the contract will be established after signing and stamping or fingerprinting. Therefore, if there is no agreement in the contract that the contract needs to be signed and sealed to be valid, then the signed contract is also valid.

Legal basis: Article 490 of the Civil Code of People's Republic of China (PRC). 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.