Abstract:A theoretical framework of the control rights defense mechanism is set up firstly,and then the model is verified with the case of Vanke’s control rights defense to Baoneng.Conclusions indicate the followings: (1) Based on symbiosis hypothesis,the design of control rights defense mechanism in advance (preventive) and in progress (active) are separately determined by Firm-specific and M&A’s path characteristics.(2) To prevent the control rights defenses protect managers excessively,it is necessary to set a balance mechanism to maintain a symbiotic relationship.(3) The design of control rights defense mechanism is also influenced by the institutional environment,and needs to be improved along with changes of firm-specific characteristics,institutional environment and M&A’s path characteristics.This paper makes a breakthrough in the existing company control rights defenses frameworks and offers some references to the design of control rights defenses mechanism for China’s listed companies.