If a written contract is concluded without signature, it generally has no legal effect. Due to the different ways of making a contract, the legal provisions are different, and the time when the contract is established is also different. A contract is established when the offer is made through a conversation (verbal or telephone) and the offeree immediately accepts the offer. The establishment time of a contract concluded by letter or telegram shall be the time when the receipt is issued when the offeror receives the promised letter or telegram. Article 490 of the "People's Republic of China and Civil Code" If the parties conclude a contract in the form of a contract, the contract shall be established when both parties sign, seal or fingerprint. Before signing, sealing or fingerprinting, one party has performed its main obligations and the contract is established when the other party accepts it. Laws and administrative regulations stipulate or the parties agree that a contract should be concluded in written form. If the parties do not use written form but one party has performed its main obligations and the other party accepts it, the contract is established. Article 143 of the "People's Republic of China and Civil Code" is valid for civil legal acts that meet the following conditions: (1) The actor has the corresponding capacity for civil conduct; (2) The expression of intention is true; (3) It does not violate The mandatory provisions of laws and administrative regulations do not violate public order and good customs.