During the period of patent validity, the patentee can flexibly authorize different objects to implement the patented technology in different scope, which will bring considerable benefits to the patentee. According to this range, patent licensing methods can be divided into five categories: exclusive license, exclusive license, general license, sub-license and cross-license. Its effectiveness order is: exclusive license > exclusive license > general license = sub-license. The legal effect of cross-licensing depends on whether the licensing agreement is exclusive or not. If it is exclusive, the effect is equivalent to an exclusive license, otherwise it is equivalent to a general license.