The signing of the contract is only valid if it is signed unilaterally. A contract is an agreement on the relationship between the rights and obligations of both parties, and it is the embodiment of the consensus of both parties, so the contract needs to be signed by both parties, otherwise it will not take effect. According to the law, if the parties conclude a contract in the form of a contract, the contract will be established when both parties sign or seal it. Article 490 of the Civil Code stipulates that 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. (1) The universal binding force of a contract on the parties. A legally established contract is legally binding on the parties. The parties shall perform their obligations as agreed, and shall not alter or terminate the contract without authorization. (2) the validity of the contract. A legally established contract shall take effect upon its establishment. The validity of a contract is reflected in the legal effect produced by the conclusion of a contract by two parties. The validity of each contract is specific, and the validity of each contract is different. (1) Concluding a contract by means of fraud or coercion, which harms the interests of the state. The so-called fraud means that one party deliberately informs the other party of false information or deliberately conceals real information to induce the other party to make a wrong expression of intention. The contract concluded by fraud is based on the fraudster's misunderstanding of fraud. The so-called coercion is to force the other party to act against the true meaning by threatening to damage the life and health, honor, reputation and property of citizens and their relatives and friends or the honor, reputation and property of legal persons. Coercion is also one of the reasons that affect the validity of the contract. A contract concluded by one party by fraud or coercion is invalid only if it harms the interests of the state. (2) contracts that collude in bad faith and harm the interests of the state, the collective or a third party. The so-called malicious collusion means that the parties collude with each other to achieve a certain purpose, thus harming the interests of the state, the collective or the third party. Contracts that maliciously collude to harm the interests of the state, the collective or the third party are common in judicial practice, mainly because the debtor enters into false sales contracts, false mortgage contracts or false gift contracts with the other party in order to avoid execution; Enterprise executives or controlling shareholders use related enterprise transactions to harm the company's interests; The debtor and the creditor collude maliciously to defraud the guarantee, etc. (3) A contract that covers up an illegal purpose in a legal form and a contract that covers up an illegal purpose in a legal form shall meet the following conditions: First, the real purpose or means to be achieved by the parties must be prohibited by laws and administrative regulations; Second, the parties to the contract have the intention to evade the law; Third, in order to evade the mandatory provisions of laws and administrative regulations, the parties take legal forms to cover up illegal purposes. (4) Laws and administrative regulations have no explicit provisions on contracts that harm the public interest, but if the contract obviously harms the public interest, the clause of "harming the public interest" can be applied to confirm that the contract is invalid. (5) A contract that violates the mandatory provisions of laws and administrative regulations, or a contract that violates the mandatory provisions of laws and administrative regulations, refers to a contract in which the parties violate the mandatory provisions of laws and administrative regulations in the purpose and content of concluding a contract. The people's court shall confirm that the contract is invalid on the basis of laws formulated by the National People's Congress and its Standing Committee and administrative regulations formulated by the State Council, and shall not be based on local regulations and administrative rules. Clauses that exempt one party from liability, aggravate the other party's liability and exclude the other party's main rights are invalid. Except for the general circumstances that lead to the invalidity of the contract, in view of the particularity of the standard terms, if the party providing the standard terms exempts the other party from its responsibilities, aggravates the other party's responsibilities and excludes the other party's main rights, the terms are invalid. It should be pointed out that if the invalidity of one or part of the format clauses does not affect the validity of other parts, the other parts are still valid.

Legal objectivity:

People's Republic of China (PRC) Civil Code

Article 490

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. 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.