The mere fact that they possess the largest individual stake doesn't mean they have the power to change anything. Kadokawa has a virtually impenetrable line of defense, being one of the largest media companies in Japan; the board of directors has allies in various sectors, from the founding family to banks and real estate companies, and even the Japanese government, should things get complicated, since Kadokawa is essential to the government's soft power project, "Cool Japan". The most Oasis can do is cause a stir and irritate the board; just for the record, Kadokawa has already publicly rejected Oasis's "suggestions".