What does it mean that there is no patent right for patent inquiry?

Those who have no patent right have been granted rights before, but they have no rights later. There may be the following situations:

1, the patent protection period expires (20 years of invention, utility model and design 10 year)

This patent was declared invalid. (After the patent is granted, others can find the technology before the patent and request China National Intellectual Property Administration to declare it invalid. )

If you don't pay the patent annual fee, the patent will have an annual fee every year. If it is not paid, the patent will be terminated.