Abstract: Patent invalidation is an effective tool for adjusting patent examination errors and optimizing patent quality. However, the utilization rate of China's patent invalidation system is at a low level and it is unable to achieve its function.Therefore, how to increase the probability of patent invalidation requests becomes a key issue in improving the utilization rate of the patent invalidation system. For the convenience of research, we define the probability of a request for patent invalidation as patent invalidation propensity, and propose what factors will affect and how to affect it. In this regard, we introduce transaction cost theory to explain the institutional logic and economic principles of patent invalidation propensity. According to the litigation dispute selection model, we propose the five determinants that affect the patent invalidation propensity, including the legal stability of patent, litigation expectation, cost of the patent invalidation, the market value of patents, and degree of information asymmetry.Furthermore, we collect 671 invention patent infringement lawsuits announced in 2019 through the Wolters Kluwer advanced law database and incoPat patent database. Meanwhile, five proxy variables, namely the patent invalidation experience, patent damages, type of party, scale of patent family,and claim, are selected as independent variables, and the Logistic regression model is used to conduct an empirical analysis of the influencing factors of patent invalidation propensity in litigation. The research finds that the legal stability of the patent and the cost of patent invalidation weaken the defendant’s patent invalidation propensity, while the plaintiff’s expectation of litigation and the market value of the patent promoted it. The degree of information asymmetry has no significant correlation with it.Finally, it concludes that China should ensure that patent holders realize their reasonably expected benefits in litigation, establish reasonable cost compensation or transfer rules for patent invalidation, and also focus on the effect of high-quality patent cultivation and promotion of patent technology transfer and commercialization to enhance or play the role of patent market value. The theoretical contributions of this study are as follows. First, we apply the transaction cost theory to the research on the patent invalidation propensity in patent infringement litigation, verify the validity of the theory in this situation, and broaden the application scenarios of the theory. Second, the influencing factors and mechanism of patent invalidation propensity are explored from the three dimensions of patent characteristics, meanwhile, the behavioral logic of the patent invalidation request also is clarified, which enriches the domestic empirical study referring to patent invalidation. Third, the results of this study also show that the information asymmetry in the context of China's patent infringement litigation has not affected the propensity of patent invalidation, which is a supplement and an amendment to the existing literature. In terms of practical contribution, we believe that clarifying the influencing factors of invalidation propensity in patent infringement litigation can help increase the utilization rate of the patent invalidation system, ensure the function of modifying patent examination errors and achieve the goal of optimizing the patent quality in China.