Is it valid to sign the pre-sale contract after the house is delivered?

Whether the pre-sale contract is valid or not depends on different situations. If the developer's "five certificates" are complete, the pre-sale contract is valid. If the developer does not have "five certificates", then the developer's behavior violates the mandatory provisions of the law, and the pre-sale contract signed is also invalid. Article 7 of the Measures for the Administration of Commercial Housing Sales shall meet the following conditions: (1) The real estate development enterprise that sells commercial housing now shall have the Business License of Enterprise as a Legal Person and the Qualification Certificate of Real Estate Development Enterprise; (2) Obtaining a land use right certificate or a land use approval document; (3) Holding a construction project planning permit and a construction permit; (4) It has passed the completion acceptance; (five) the demolition and resettlement has been implemented; (six) water supply, power supply, heating, gas, communications and other supporting infrastructure have delivery conditions, other supporting infrastructure and public facilities have delivery conditions or the construction progress and delivery date have been determined; (seven) the property management plan has been implemented.