Capital Market Evaluation of the Stock Option Plans in Japan

在1997年9月底的股东大会上，东京证券交易所第一部分通过了授予库存股类型股票期权的决议，对上市公司的股价反应进行了审查。当时有15家公司。在批准采纳股票期权计划的董事会议的下一个交易日，平均超额收益在统计上并不显著。不是将样本限制在前15家公司，而是以相同的方式计算84个样本的异常收益，这些样本在1998年之前推出了股票期权计划和/或准股票期权计划。随着数据数量的增加，异常收益变得显著。1997年5月28日，东京证券交易所发布了及时披露建议。然而，到那时，首批15家公司中已有13家公司批准在董事会议上引入股票期权。S…更重要的是，第二天的董事会议不是正确的事件日。用公告日代替第二天的董事会议，即使对前15家公司也可以观察到显著的t值。及时披露规则的修订跟不上《商法典》修订的速度，造成了资本市场的某种混乱。由于在公司的薪酬计划中采用股票期权计划似乎是一个好消息，应该及时发布，以避免资本市场的混乱。2001年，日本商法典进行了修改，将管理可转换债券、股票认购权证发行的债券和股票期权的条款合并在一起，因为这些都是公司发行的看涨期权。虽然《商法典》不再限制授予股票期权的数量，但对有资格享受所得税优惠的限制似乎限制了授予员工的股票期权数量。较少

The reaction of the share price was examined for the listed corporations at the First Section of the Tokyo Stock Exchange that approved the resolution to grant treasury stock type stock options at the shareholders' meeting by the end of September 1997. There were fifteen corporations. The average abnormal return on the next trading day of the directors' meeting that approved the adoption of stock option plans was not statistically significant. Instead of limiting samples to the first fifteen corporations, the abnormal returns was calculated in the same manner for eighty four samples, which introduced stock option plans and/or quasi-stock option plans by 1998. By increasing the number of data, abnormal returns became significant.It was on May 28, 1997, when the recommendation for timely disclosure was issued from Tokyo Stock Exchange. However, by then, thirteen corporations among the first fifteen corporations have already approved to introduce stock options at the directors' meeting. S … More o the next day of the directors' meeting was not the correct event day. By using the announcement date instead of the next day of the directors' meeting, significant t value can be observed even for the first fifteen corporations. The amendment of the rule for the timely disclosure could not catch up with the speed of the amendment of the Commercial Code, which caused in some kind of confusion in the capital market. As the adoption of stock option plans in the compensation program in the company seems to be a good news, which should be released timely in order to avoid the confusion in the capital market.In 2001, Japanese Commercial Code was amended to combine the articles that regulates convertible bonds, bonds issued with stock purchase warrants, and stock options, as those are all call options issued by the company. Although the Commercial Code no longer limits the number of stock options to be granted, the restriction to be eligible for the preferential treatment for the income tax seems to restrict the number of stock options to be granted to the employees. Less