深化混合所有制改革与实施创新驱动发展战略背景下，探讨国有控股权变化对企业创新的影响具有重要现实意义。以2009—2020年沪深A股上市公司为样本，采用精确断点回归方法分析企业国有控股权变化对企业创新的因果效应，结果发现：总体而言，国有股权由非绝对控股变为绝对控股会对企业创新产生显著正向激励作用；在区分不同动机创新行为后，该作用依然显著，且对策略性创新的激励作用明显强于实质性创新。此外，在不同市场结构中，国有股权由非绝对控股变为绝对控股对不同动机企业创新具有异质性影响。结论可揭示国有股权控股地位变化对企业创新的因果效应，厘清国有控股权在企业创新驱动过程中的作用，进而为混合所有制改革背景下企业所有权结构选择与优化提供实证证据。

Innovation is an essential factor for obtaining core competitive advantages and achieving long-term value. Particularly in emerging and rapidly growing countries where the globalization of emerging markets brings pressure and opportunities for domestic firms, such as China, a high level of corporate innovation is a dominant factor in driving economic development. In recent years, China has implemented policies for innovation-driven development strategies and issued a series of regulations to stimulate corporate innovation. Enterprises are important subjects of innovation. State-owned enterprises (SOEs) are an important part of Chinese enterprises. Enhancing the corporate innovation capability of SOEs is a key initiative to implement the innovation-driven development strategy and an important goal of the mixed-ownership reform of Chinese SOEs. The shareholding structure is a fundamental institutional arrangement in an enterprise, and has an important impact on the choice of innovation strategy. Innovation involves substantial resource investment and is characterized by long-term cycles and high uncertainty, making it challenging for firms to support innovation with their resources. In emerging economies, such as China, where capital markets are not well developed, firms have limited access to innovation resources from external sources. In this situation, state ownership with actual government control is particularly crucial for corporate innovation. Hence, it is significant to examine the effect of state ownership (especially the absolute control of state ownership) on corporate innovation in the context of SOE mixed-ownership reform.#br#Therefore, this paper employs the sharp regression discontinuity (Sharp RD) method to investigate the causal effect of the change in state ownership absolute control position and corporate innovation using a sample of A-share listed companies in Shanghai and Shenzhen from 2009—2020. The results of the study are as follows. First, the change in state ownership from a non-absolute control position to an absolute control position generally has a significant positive incentive effect on corporate innovation. Second, after distinguishing between different motivations for corporate innovation, the change in state ownership from a non-absolute control position to an absolute control position promotes strategic and substantive innovation. Moreover, the incentive effect of the change in state ownership from a non-absolute control position to an absolute control position on strategic innovation is significantly stronger than that of substantive innovation. Third, there are heterogeneous effects of the change in state ownership from a non-absolute control position to an absolute control position on corporate innovation in different market structures. Specifically, in the monopolistic industry, the change in state ownership from a non-absolute control position to an absolute control position does not significantly affect corporate strategic innovation but significantly promotes substantive innovation. In the non-monopolistic industry, the change in state ownership from a non-absolute control position to an absolute control position promotes corporate strategic and substantive innovation, and the promotion of strategic innovation is significantly stronger than substantive innovation. The above findings are still significant after taking a continuity hypothesis test, adding covariates, nonparametric regression discontinuity and other robustness tests.#br#The main contributions of this study in comparison with the existing literature lie in three aspects. First, this paper focuses on the impact of the change in state ownership from a non-absolute control position to an absolute control position on corporate innovation. It clarifies the relationship between state-owned holding and corporate innovation from the perspective of policy pressure and shareholding checks and balances, providing reference for promoting SOE mixed-ownership reform and implementing innovation-driven development strategies in China. Second, this paper classifies corporate innovation into strategic and substantive innovation based on different motivations and further explores the effects of the change in state ownership from a non-absolute control position to an absolute control position on strategic and substantive innovation. It further explains the causes of the "high-quantity and low-quality" of Chinese patents and provides suggestions for improving the quality of Chinese innovation. Third, this paper examines the heterogeneous effects of the change in state ownership from a non-absolute control position to an absolute control position on corporate innovation with different motivations in different external market structures by using a Sharp RD method. The findings provide empirical evidence for constructing different optimal control structures that contribute to corporate substantive innovation in different market structures.#br#