中文摘要：

以汤臣倍健为例,结合股票期权激励计划草案公告日前后股票累计超额收益的分布特征,以及股票期权激励计划草案推出后信息披露特征,对股票期权激励计划推出环节机会主义择时行为进行了研究。研究发现,股票期权激励计划草案公告前存在显著的负累积超额收益,而在草案公告后存在显著的正累积超额收益,结果表明公司管理层为了获得一个较低的行权价格在股票期权激励计划推出环节实施了机会主义择时行为。结果意味着,要想使得股票期权激励达到预期的效果,不仅要重视股票期权激励计划实施环节的有效性,而且要关注股票期权激励计划制定环节的有效性,规范行权价格的确定机制,优化公司治理结构,对于保证股票期权激励不至于沦为代理问题来源具有非常重要的意义。

英文摘要：

Taking BY--HEALTH as an example, the launched link opportunistic timing behavior of stock option incentive scheme is studied based on the distribution characteristics of stock cumulative excess returns during the announcement date of stock option incentive plan and the information disclosure characteristics after the introduction of the draft plan. The results show that the draft plan has significantly negative cumulative abnormal return prior to the announcement, while it has significantly positive cumulative abnormal return after the announcement of the draft, which indicates the company management has carried out opportunistic timing behavior during the stock option incentive plan being launched for the sake of obtaining a lower exercise price. The results also imply that both the implementation effectiveness and the effectiveness of plan making process of stock option incentive plan should be concerned about in order to make the stock options incentive achieve the desired effect. It has very important significance to regulate the exercise price determining mechanism and optimize corporate governance structure so as to guarantee incentive stock option not to become the source of agency problems.