Acquiring e-books suppliers authorization is not only the basis of using e-books for libraries but also the precondition of using e-books by library users. In recent years,in order to pursuit more business interests,many e-books suppliers add some licensing restrictions,which affect the development of e-lending services of libraries. This paper analyzes the application status quo of copyright authorization mode of library e-books,finds the existing problems,puts forward the strategy of optimizing the existing unreasonable authorization mode,and provides a valuable reference for the promotion of library e-books service and the development of the e-books industry ecosystem.

    The publishing,market and usage of e-books involve many interest groups such as authors,publishers,aggregators,self-publishers,wholesalers,agents,libraries and users. The copyright of e-books has been changed from authors to other authorized main groups. According to the difference of library e-books platform managers,library e-books copyright authorization chains can be divided into three modes,namely aggregator-led,publisher-led and library-led modes. On the basis of the analysis of the authorized chain,the copyright authorization mode of library e-books is classified into single-user,multi-user and hybrid-user with seven types. Different modes and types have their own characteristics.

    Taking the United States and China as example,the paper explores the application of the current situation of the library e-books copyright authorization mode,and finds that there are obvious differences in different types of library e-books license terms in America. Single-user mode is widely used in public libraries,and multi-user mode is the most widely used mode in the primary and secondary school libraries. The e-books provider's licensing restrictions for public libraries are much more stringent than for the primary and secondary school libraries. Compared with America,multi-user subscription is the main type of copyright authorization mode in China；there is fewer types and licensing restrictions than in America,but the number of the new e-books of our country is obviously inadequate.

    The study finds that the current copyright authorization mode of library e-books is mainly controlled by the e-books suppliers. The multi-user permanent access mode that the library is most willing to use is not supported by the suppliers,which has a negative impact on the construction and service of library e-books resources. A variety of licensing restrictions prevent users using e-books,and the authorization model is far away from meeting the demand of users. It is believed that the establishment of a reasonable mode of copyright authorization needs the interest groups to establish the ecological view of thinking,and compromise in the process of the interest game. The libraries,representing the interests of the users,should stand for the public interest and adhere to the concept of freedom of information acquisition and promote users using e-books. Four strategies are proposed to optimize the e-books authorization mode,including promoting government-led practices in the development of e-books authorization mechanism,making full use of the role of library associations,strengthening and pursuing win-win cooperation with multiple stakeholders,and improving competition mechanism of e-books market. 4 figs. 32 refs.