Robert Addison Day Jr.

Age: 54

Net Worth: $500 million

Source of Wealth: Money management

Residence: Los Angeles

After weighing merger proposals in 1996, Robert Addison Day Jr. decided last year to continue running Los Angeles-based Trust Co. of the West as an independent, privately owned company. Bidders were rumored to have offered only $500 million to $600 million (TCW’s total assets have slipped in the past couple of years, as the firm got out of poor-performing funds).

Day’s maternal grandfather was Superior Oil founder William M. Keck. On his father’s side, he is the grandson of Addison Day, onetime president of Los Angeles Gas Co.

After studying at Claremont McKenna College, he started TCW in 1972 with $1.5 million from investors. TCW is employee and director-owned, with Day the largest individual owner.

In 1996, Day succeeded his uncle, the late Howard B. Beck, as chairman and president of the W.M. Keck Foundation, one of the nation’s largest philanthropic organizations with $1.2 billion in assets. Under the leadership of Day and Beck, the foundation has made grants of $550 million, mostly in the areas of medical research, science, and engineering.