Is it reliable to buy patents on Taobao?

Not very reliable. Because you need to go through the formalities of transfer registration when purchasing a patent, you need to go through the formalities in China National Intellectual Property Administration. If the other party can help you with the formalities, you can still consider the transfer formalities. China National Intellectual Property Administration's website has published all patents, and the information of the obligee, including the address, will be made public. If you are interested in a patent, you can directly contact the right holder at the corresponding address.