Using a unique, hand-collected data sample and panel-data econometric techniques, we analyse the impact of founding-family control and intergenerational succession on the value of Chilean listed companies. After controlling for firm- and ownership-specific characteristics, we find an inverse U-shaped relationship between a founding family’s degree of ownership and firm value. Hence, family ownership at first increases firm value. However, when family ownership exceeds a threshold of about 38 percent of outstanding shares, the family takes advantage of its power in the firm and extracts wealth from minority shareholders. Further, if the founder of the company is the CEO or chairman of the board, firm value increases. However, family businesses with a subsequent-generation owner-manager destroy value.