Invention patents have regional protection restrictions. In other words, U.S. patents are protected in the United States. Chinese inventions are protected in China. . If American inventions are to be sold to China. Either it applies for patent protection in China, or it has no patent in China. Then you can sell them all. . It just depends on whether the product has applied for invention patent protection in China. . Or you can design and write a patent document for this product, and try to declare an invention. . If you can declare it. Then you can produce and sell it at will in the country. . In addition, if the American machine has a trademark, you should also check that the trademark has not been registered in China. If you haven't registered it, then you have to register it, and American products cannot be sold in China. . If trademarks and patents are owned by you in China, then you can produce and sell products under this brand at will.