If a certain brand of goods is sold online, it is not infringing if it is authorized or purchased from formal channels and has the right to resell. However, if you privately sell branded products from unknown purchase channels or sell fake and inferior products, it will constitute infringement. Article 57 of the "Trademark Law of the People's Republic of China" includes any of the following acts, which shall infringe the exclusive rights of a registered trademark: (1) Using the same kind of goods as the registered trademark without the permission of the registrant of the trademark (2) Using a trademark that is similar to the registered trademark on the same product without the permission of the trademark registrant, or using a trademark that is the same or similar to the registered trademark on similar products, which is likely to cause confusion; (3) Selling goods that infringe the exclusive rights of registered trademarks; (4) Forging or manufacturing registered trademarks of others without authorization or selling counterfeit or unauthorized registered trademarks; (5) Changing the registered trademark without the consent of the trademark registrant and puts the goods with the changed trademark back into the market; (6) Deliberately providing facilities for infringement of the exclusive rights of others' trademarks and helping others to infringe the exclusive rights of trademarks; (7) Causing other damage to others' exclusive rights to registered trademarks of.