일본 회사법에 있어서의 주식제도와 코포레이트 거버넌스 － 신주예약권제도의 활용을 중심으로 －

In the view of legitimateness of M&A defence system, if the purpose beforehand or afterwards remains same, the legal evaluation would be considered same. However, the situation refers a big difference depending on beforehand or afterwards. In the defence system after struggle for control is occurred, the certain shareholder who became the majority shareholder might be disadvantageous. In the beforehand defence system, there would not be any certain shareholder who would be disadvantageous as referred the same meaning. In consideration of a person who will be a future shareholder as an investor, not a shareholder, he is not a subject to protect its direct interest under company law. In the point of view to protect the investor from a hostile takeover, if an opportunity to consider whether they continue to invest expecting a risk or stop to invest are given by notifying the defence system beforehand, it is certain that chances for damage will be decreased. In case of the beforehand defence system, there is a benefit having a sufficient time to concern the shareholder's determination throughout approval of general meeting of shareholder on introducing the defence system. Under this circumstance, build the beforehand defence system extends a scope that the legitimate defence system would be initiated. On the other hand, the beforehand defence system reveals a problem being abused because the hostile takeover which is the subject to be defence is not specified. The beforehand defence system is able to allow the hostile takeover for the company's benefit according to its structure. As a result, it effects to hesitate buying related to the company's benefit, and therefore, it could be used for an excessive wide range of the defence system. In case of the afterwards defence system, a judicial review could be taken on the legitimateness of defence regarding the certain hostile takeover. In comparison, a strong beforehand defence system such as issuing a call option in advance, there is a high possibility that the scope to proceed the judicial review such on a period of filing a lawsuit would be narrowed down although there was an unfair management at the time allowing the hostile takeover. Due to this, the company blocks the beneficial buying under its duty to defence the disadvantageous buying and raises a possibility used it as self protection for management.