The negative impact of non patent entities（patent trolls） is not small, but they can also promote innovation, while the patent entities may also engage in the act of patent trolls. According to the existing patent system, non-practiced patents are legal, and the key to solve the problem of non-practiced patents is not to distinguish between patent entities and non patent entities, but rather to distinguish between non-practical patents and non patent entities. The patent troll problem is essentially a non-practiced patent problem. The actual use of the patents can reduce the negative effects of the patent trolls and maintain the positive role of the patent trolls.
the paper patent doctrine