Abstract: The rapid development of the digital economy and big data has caused an explosive growth in the amount of data in society. At the same time, data monopoly has become an important issue affecting the healthy development of the economy and society. Through literature analysis, model construction and case analysis, starting from the classification of data monopoly, the impact of data monopoly and its response are analyzed. The following conclusions are drawn: Firstly, it defines data monopoly separately from public data and commercial data, and divides data monopoly into four types: public data development type, public data monopoly type, commercial data development type and commercial data monopoly type; Secondly, the impact of data monopoly on the economy and society can be divided into two aspects: positive and negative. Different types of impacts are different. The policy measures that should be adopted are focused on strengthening data disclosure and sharing, establishing a data right confirmation mechanism, maintaining normal market competition, and afterwards supervision shifting to ex-ante supervision; Thirdly, based on the degree of data collection and marketization, a theoretical model of data monopoly classification is constructed.

Key words: Data monopoly, Classification model, Business data, Public data, Data sharing, Data right confirmation, Digital economy