Theoretically it is not possible, but it depends on whether the claims are written in place. If there are loopholes, you can apply for a similar patent based on the loopholes, or you can apply for another new patent with some modifications. It is still possible. Buying patent rights or investing in technology shares should be discussed with the parties involved. The patent is valid for 20 years, and upon expiration of 20 years it enters the public domain. The rights of the patentee include: ① exclusive right to implement; ② right to import; ③ right to transfer; ④ right to license; ⑤ right to relinquish; ⑥ right to mark; ⑦ right to pledge. The obligation of the patentee is to pay annual patent fees (also called patent maintenance fees). The Patent Law stipulates that any person who uses, manufactures, sells, offers to sell, or imports patented products for business purposes without the permission of the patentee shall be guilty of infringement. Design patents may not be manufactured, sold, or imported.