Legal analysis: after receiving the letter from the infringement lawyer, try to check the products produced and sold by yourself in view of the infringement mentioned in the letter. If there is any infringement, it is best to entrust a lawyer in time and actively contact the obligee or the opposing lawyer for consultation. If it is a legal channel product, you can provide a sales contract and a supply list. If you didn't know it was an infringing product before, you can stop selling it now. The following conditions can prove that the commodity is legally obtained by itself: (1) There is a supply list and payment receipt legally signed by the supplier and verified or recognized by the supplier; (2) There is a procurement contract signed between the supplier and the supplier, which has been verified to have been truly fulfilled; (3) There are legal purchase invoices and the items recorded in the invoices correspond to the commodities involved; (4) Other circumstances that can prove the legal acquisition of the commodities involved.

Legal basis: Article 80 of the Regulations on the Implementation of the Trademark Law of People's Republic of China (PRC). If it can be proved that the goods were legally obtained by itself and the supplier can be proved, the administrative department for industry and commerce shall order it to stop selling and notify the administrative department for industry and commerce where the supplier of the infringing goods is located.