If the legal person does not sign and affix the official seal, it is valid if the law does not stipulate that it must be signed or the parties do not stipulate that it must be signed. The legal representative can choose to sign, seal or print the contract according to law, and all the above methods are valid, without special provisions or agreements. 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.

The responsibility of an enterprise as a legal person is:

1, responsible for the company's debts;

2. Take administrative responsibility for the company's violations of laws and regulations, and bear criminal responsibility if the circumstances are serious;

3, the legal representative of the above behavior according to the fault to bear the corresponding responsibility.

To sum up, a contract shall be concluded in writing in accordance with the provisions of laws and administrative regulations or the agreement of the parties. If the parties have not concluded a contract in writing, but one party has fulfilled its main obligations and the other party has accepted it, the contract is established.

Legal basis:

Article 143 of the Civil Code of People's Republic of China (PRC)

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

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.

Article 502

A legally established contract shall come into force upon its establishment, except as otherwise provided by law or agreed by the parties.

In accordance with the provisions of laws and administrative regulations, if the contract should go through the approval procedures, such provisions shall prevail. If the failure to go through the formalities such as approval affects the effectiveness of the contract, it will not affect the performance of the obligation clauses such as approval and the effectiveness of relevant clauses in the contract. If the party that should go through the formalities for approval fails to perform its obligations, the other party may require it to bear the responsibility for violating its obligations.