A group of patent documents linked by at least one * * * is called a patent family. Each patent document in the same patent family is called a member of the patent family, and each patent in the same patent family is a patent of the same patent family. The patent document with the earliest priority in the same patent family is called basic patent. In fact, to put it bluntly, it is a patent family composed of patents with exactly the same content applied in different countries.
Then apply, for example, to apply for a patent that has been applied for in other countries when there is no such patent in one country. If you know the patent, you can copy it repeatedly and apply for a patent in this country. As long as you have a novel patent, you will be authorized. So the patent family exists in this way, but with the trend of globalization, the number of family members is gradually decreasing.