The valid conditions of this contract are:
1. The contractor has more than two parties;
The contract signed by both parties must be performed according to law. If the contract concluded by the parties violates the requirements of laws and administrative regulations, the law will not recognize and protect it;
3. The parties must agree on the main terms of the contract, and the contract must be agreed by both parties;
4, the establishment of the contract should have an offer and acceptance stage, the establishment of the contract is from the negotiation between the parties to the contract, the contract offer and acceptance to reach an agreement.