Before applying for a design patent, there were already products in circulation in the market. Is this patent still valid?

Whether it is effective or not is decided by the state administration. As long as the patent is granted and not declared invalid, then the patent is not invalid or invalid. However, before the patent application date, the same product already existed in the market, which may lead to two consequences. First, the manufacturer who produces the same product can make a defense on the grounds of the existing design to prove that his product has not infringed the patent right (provided that strong evidence can be given to prove that the product was sold in the market earlier than the patent application date). Another consequence is that if others want to file an invalid application for this patent, they can claim that the patent is not novel on the grounds that the listed product is earlier than the patent application date.