valid, but the other party must have the signature of the legal representative. Article 44 of the Contract Law stipulates that a legally established contract shall take effect upon its establishment. However, the establishment of a contract does not mean that the contract takes effect, because only a legally established contract can take effect. The contract is valid without the official seal of the unit but with the signature of the legal representative. 1. The contract is established when the signature and seal meet one requirement. Article 32 of the Contract Law stipulates: "If the parties conclude a contract in the form of a contract, the contract is established when both parties sign or seal it." 2. The power of attorney is signed and sealed by Party B, and the entrustment is established and the contract is valid. If there is no signature and seal of Party B, the validity of the contract is to be determined, and the contract is valid if Party B ratifies it, and the contract is invalid if Party B refuses to ratify it. Valid, but the other party must have the signature of the legal representative. Article 44 of the Contract Law stipulates that a legally established contract shall take effect upon its establishment. However, the establishment of a contract does not mean that the contract takes effect, because only a legally established contract can take effect. The contract is valid without the official seal of the unit but with the signature of the legal representative. Unqualified. It is regarded as a blank paper to sign first, and how to write the text as a result, only one side of the word, can not be regarded as a joint discussion between the two sides. Signing at the end of the contract means that both parties have no objection after reading it. It can be said that a substandard contract is invalid. For reference. 1. If the contract is signed by the entrusted agent of the unit within the scope of his authority or the legal representative of the unit, the contract is valid. 2. If the signed entrusted agent does not have the power of attorney, exceeds the power of attorney or signs the contract after the power of attorney is terminated, the signed contract will be valid after ratification by the principal. Without ratification, the contract is invalid and the actor shall bear civil liability. If I know that someone else has committed a civil act in my name without denying it, it shall be regarded as consent. Article 38 In accordance with the law or the articles of association of a legal person, the person in charge who exercises functions and powers on behalf of the legal person is the legal representative of the legal person. Article 63 Citizens and legal persons may carry out civil juristic acts through agents. An agent carries out civil legal acts in the name of the principal within the scope of agency authority. The principal shall bear civil liability for the agent's agency behavior. Article 66 An act without agency, beyond agency or after the termination of agency shall only be ratified by the principal, and the principal shall bear civil liability. If an act is not ratified, the actor shall bear civil liability. If I know that someone else has committed a civil act in my name without denying it, it shall be regarded as consent. Two or more parties to a contract or agreement can freely agree on the effective conditions of the contract or agreement, including only stamping or signing, stamping and signing, signing and authorization, and so on. The parties can not only agree on the form of signing as a condition of entry into force, but also agree on a certain period or a special situation as a condition of entry into force. 1. Only the unit seals, and no one signs on behalf of the company. Because the administrative seal and contract seal of a unit can fully represent a company, a contract or agreement with the company's seal is enough to be recognized as the true meaning of the company. The seal here should be a seal that has been applied for engraving by the public security organ and put on record. If it is a private seal, it cannot represent the company in principle. At the same time, the private engraver and user of the official seal should be investigated for corresponding administrative responsibility and even criminal responsibility. In judicial practice, the people's court generally adopts the principle of "recognizing the seal but not the person" to judge the validity of the contract. Therefore, any unit should strictly supervise the seal to avoid a small mistake that will cause irreparable losses to its own unit. 2. Only the legal representative signs, and no unit seals. Article 32 of the Contract Law of the People's Republic of China stipulates: "If the parties conclude a contract in the form of a contract, the contract is established when both parties sign or seal it." According to this understanding, it seems that a contract signed and not sealed by the legal representative is not established. However, Articles 9 and 5 of the Contract Law of the People's Republic of China respectively stipulate: "When concluding a contract, the parties shall have corresponding capacity for civil rights and capacity for civil conduct. The parties may entrust an agent to conclude a contract according to law. " "A contract concluded by the legal representative or person in charge of a legal person or other organization beyond its authority is valid unless the other party knows or should know that it is beyond its authority." Thus, when a legal representative exercises authority on behalf of a legal person, it should generally be regarded as having corresponding capacity for civil rights and capacity for civil conduct, and his representative's behavior is valid. The legal person should bear the responsibility for his external behavior in the name of a legal person, and the official seal is not a necessary condition for the establishment of a contract. Therefore, although only the legal representative or person-in-charge has signed it without the seal of the unit, as long as the legal representative or person-in-charge of the unit has registered in the relevant registration, it will have publicity power to the outside world, and the act of signing relevant contracts and agreements on behalf of the unit should be regarded as the act of the unit, and the unit should bear civil liability for it. 3. Only the head of the department signs, but no unit seals. Generally speaking, the department heads of an organization are all appointed by the company, and they are not displayed in the registration information, so they have no publicity effect, and the signature of the department heads cannot represent the organization of course. If it is necessary to make its signature act effective for a third party, there must be a special authorization, that is, the unit should issue a power of attorney for it, indicating the affairs entrusted to it, the scope of authority, the deadline of authority, etc., and affix the seal of the unit. The signatory should keep the power of attorney as an annex to the contract, so that its signature act is legal and effective. 4, both the unit seal, and the legal representative or person in charge of the signature. Such a contract or agreement signing form is valid. 5. Both the unit seal and the signature of the department head or representative. Such a contract or agreement signing form is valid. 6, no unit seal, and no one signed. In practice, this situation may occur. Although the two parties have drawn up a contract and passed it on to each other for approval, they have not signed or sealed it. One party has fulfilled the main obligations of the contract and the other party has accepted the performance of the other party. Then the contract should be established and come into effect, but the effectiveness of the contract is not based on the written contract itself, but on the performance of both parties. According to the above specific signature or seal, we can know whether the contract is effective or not. The contract is valid if it is stamped with the official seal and not signed. Article 32 of the Contract Law; "If the parties conclude a contract in the form of a contract, the contract shall be established when both parties sign or seal it." Generally speaking, a contract is valid only if it meets the effective conditions stipulated by law, otherwise it may not only be invalid but also be sanctioned by law. Legal evaluation of the parties' agreement, in terms of the effectiveness of the contract, is to stipulate the effective elements of the contract as the evaluation standard. Contracts that meet the valid requirements shall be given legal effect according to the agreement of the parties, while contracts that do not meet the valid requirements shall be treated as invalid, revocable or with undetermined effect according to different circumstances. The effective elements of a contract are the criteria for evaluating the agreement of the parties by law, so they should be different from the establishment elements of a contract. According to Article 55 of the General Principles of Civil Law, the effective elements of a contract should include: the actor has corresponding capacity for civil conduct; Meaning means truth; Does not violate the law or social public interests. Some special contracts may have some special effective elements, for example, contracts for foreign cooperative oil exploitation need to be approved by relevant state departments before they can take effect.