Legal analysis: the function of the riding seal is to prevent the inside page of the contract from being replaced, which will lead to the change of the contract content; Prevent the other party from denying the contents of the contract; And can avoid unnecessary disputes and losses caused by changing or denying the contents of the contract.

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 meaning 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 Where the parties conclude a contract in the form of a contract, the 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.

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.