Legal analysis: if the agreement signed by the handprint meets the requirements of effective civil juristic act, the agreement is valid.

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

Article 143 A civil juristic act that meets the following conditions is valid: (1) The actor has corresponding capacity for civil conduct; (2) the will is true; (three) does not violate the mandatory provisions of laws and administrative regulations, and does not violate public order and good customs.

Article 490 Paragraph 1 A contract is concluded by the parties in the form of a contract, and a contract is formed when the parties sign, seal or fingerprint it. Before signing, sealing or fingerprinting, one party has fulfilled its main obligations, and the contract is established when the other party accepts it.