Abstract: In recent years, employees from mature enterprises starting their own businesses is becoming a more and more common phenomenon in various industries. Founders and investors with work experience in the same mature enterprise often accumulate similar resources like technical knowledge, field experience, capital resources, social connections and so on. Thus, they could establish connections based on their previous work experience, and gradually forming a micro-level entrepreneurial ecosystem with mature enterprises as the core enterprise, enterprises or investment institutions founded by those employees as the inner core participants, and external entities as the outer opportunity space. Then, what is the essence of the enterprise ecosystem based on employee entrepreneurship? What are the structural characteristics of such an ecosystem based on employee entrepreneurship from mature enterprises? And how do these characteristics evolve over time? This research aims to answer these questions. Firstly, by reviewing the literature, this research draws on the subsidiary view component of the integrated framework of the ecosystem research perspective to construct a conceptual model of enterprise ecosystem based on three levels of core enterprise-inner core participants-outer opportunity space. Then, this research establishes an analysis framework for the evolution characteristics of the enterprise ecosystem from four ecosystem-specific dimensions: participant heterogeneity, ecosystem output, participant interdependence and non-contractual governance. Finally, the research uses quantitative statistical analysis, and selects Alibaba, whose employee entrepreneurship phenomenon and ecological characteristics are significant, as the research object, and uses descriptive statistics to summarize the evolutionary characteristics of the enterprise ecosystem from 1999 to 2020 and summarizes the patterns of change between structural characteristics in relation to the stages of development of the ecosystem. The research results show that the startups in the ecosystem benefit from the growth of the core firm, and this growth is reflected in the evolution of the structural characteristics of each dimension of the ecosystem: in the birth stage, the ecosystem has high role heterogeneity and middle attribute heterogeneity, which makes the output of the ecosystem show a low level, so the degree of internal interdependence is relatively weak, and the non-contractual governance ability with internal as the governance center is not strong; in the expansion stage, the heterogeneity of attributes increases, which drives the level of output to increase, thereby increasing the internal interdependence and improving the non-contractual governance capacity accordingly; in the leadership stage, the attribute heterogeneity of the participants increases, which leads to the improvement of the output capacity, but the growth rate slows down, the degree of dependence between the internal participants also tends to weaken, the non-contractual governance ability is no longer improved; in the self-renewal stage, the stable participant heterogeneity makes the output level of the system into a bottleneck, the dependence between internal participants decreases, and the level of non-contractual governance also decreases accordingly.

Key words: employee entrepreneurship, venture capital, entrepreneurial ecosystem, evolution characteristics, Alibaba