Big data is the basis and strategic resource of digital economy, and is an important factor of economic development in the post epidemic era. However, the theoretical cognition of big data from all walks of life still lags behind its application practice, and there are many controversies about big data right confirmation, transaction pricing, and capitalization, which form potential risks for the sustainable and healthy development of big data industry and digital economy, and also become a constraint for the development of big data industry. Data is the key to the normal transformation of production factors and participation in social production. On the basis of a new understanding of the concept and attribute of big data, this paper expounds the market logic of how big data evolves from commodity circulation factors to social production factors and the capitalization process of how the use value is injected into big data, and puts forward the legal basis of big data right confirmation and the strategy of big data exchange ecology from a practical perspective. At the same time, the transaction pricing model proposes to use data tax to make up for the small and micro rights abandoned by individuals and enterprises in the big data collection link, and transform private rights into social public products, which provides new reference for the development of big data industry and factor markets.