Abstract: The expropriation on the benefit of small shareholders by large shareholders is achieved through the latter’s collusion with manager to seek private benefits.When acting in collusion,large shareholders take more intensive supervising measures than usual.The collusion between large shareholders and manager not only leads to decrease in earnings of the small shareholders due to large shareholders’ expropriation on their due benefit,but also results in decrease in companies’ return.Requiring large shareholders to shoulder fiduciary duty is thus the major legal method to bring their acts in control.

Key words: large shareholder, collusion, private benefits, fiduciary duty