Abstract: Innovation is a high-risk investment activity. Risk taking and financing constraints are the key to enterprise innovation activities. Mixed ownership enterprises with multiple heterogeneous large shareholders are better able to take risks, ease financing constraints and promote high-quality innovation. The research finds that the innovation ability of mixed ownership enterprises with multiple heterogeneous large shareholders is significantly stronger than that of other enterprises. Further research shows that risk taking and financing constraints are intermediary variables that affect high-quality innovation of mixed ownership enterprises with multiple heterogeneous large shareholders. To be specific, the checks and balances and diversity of the heterogeneous large shareholders affect the enterprise's risk taking, thereby improving the enterprise's innovation ability. The diversity of the heterogeneous large shareholders alleviates the enterprise's financing constraints, thereby improving the enterprise's innovation ability. Moreover, the two intermediaries are more significant in high-quality innovation. The conclusion of this study shows that the coexistence of multiple heterogeneous large shareholders in a mixed ownership enterprise is conducive to the improvement of the enterprise's innovation capability, and this conclusion has important implications for the mixed ownership reform of state-owned enterprises and high-quality economic development.

Key words: multiple heterogeneous large shareholders, mixed ownership, risk taking, financing constraints, enterprise innovation