Ownership structure plays critical roles in incentives and behaviors within business organizations. The finance and accounting literature has focused on the effects of firm ownership dispersion across managers and investors. We extend the literature by examining the roles of ownership structure within a controlling family. Specifically, we focus on a family trust structure that is a popular vehicle for holding family ownership around the world. The trust structure typically locks controlling ownership within a family for a very long period. Although ensuring family control, the share transfer restriction potentially induces family shirking problems and distorts firm decisions. We find abundant such evidence based on a sample of publicly traded family firms in Hong Kong.