yeah but nintendo had the chance to buy these 51 % first, but they refused.
the real reason is that nintendo doesn't want to invest so much money into a name, cause that's all that Microsoft bought. Someone from Nintendo said that the problem with buying studios is that you have no guarantee that the talented developers stay there, and if they leave, you may have left some franchises, but those can be ruined quite fast, just look at crash or spyro.