Unocal standards are legal standards of defensive measures in hostile M & A. It was decided to judge whether UNNOCAL Petroleum of the United States would legitimately recognize Boz Pickens’s hostile M & A attack against a defensive defense-like approach such as poison pill. As a result of the battle battle with Mr. Boone · Pickens with a synonym of Unocal Oil and a takeover shop, the defensive measures used at this time were judged to be justifiable as a countermeasure against the Unocal oil side. In this way, in the case where hostile takeover poses a threat to corporate management and efficiency, a decision has been made that management side defense measures are accepted. From this case, countermeasures against poison pill were justified and came to be called Unocal standards. As a result, the “Unocal Standard” became recognized as a legal standard along with “Revlon Criteria”. Although the Leblon standard was established by the defense’s defeat, the Unocal standards can be said to have been built by the defense side’s favor.

In hostile M & A, directors should act as a shareholder agent with the aim of maximizing shareholder interests

Approximate codes of conduct of directors are clarified by two types of Unocal standards and LeBron standards, which is a relatively new way of thinking in the United States. Both are based on a ruling issued in 1985. LeBron standards showed a code of conduct that a director should act in the hostile M & A as a shareholder agent with the aim of maximizing shareholder interests. It was born by the losing of LeBron. However, the Unocal standard was born in the process that the targeted Unocal approved a poison pill method to lower the shareholding ratio of the acquiring side by issuing stock acquisition rights to existing shareholders . In the case where the hostile M & A affects the management, efficiency, etc. of the enterprise and becomes a threat, this method utilizes the property that it can exercise at a low price if certain conditions of stock acquisition rights are met It was to be recognized as a defensive measure. The perfect difference between Lebron ‘s defense measures and the defense measures taken by Unocal is that it is not a disadvantage to shareholders.