4) Mark Zuckerberg – Net Worth: $33.8 Billion

This 30 year old self made billionaire is the chairman, CEO and co-founder of the immensely popular social networking website Facebook.

3) Jim Walton – Net worth: $35.3 Billion

This 66 year old billionaire is the chairman and CEO of Walton family’s Arvest Bank Group, Inc. The bank is worth approximately $1.8 billion. Its net profit was around $100 million in 2012.

2) Charles Koch – Net worth: $41.9 Billion

This 78 year old billionaire is the chairman and CEO of Koch Industries, a post he has held since 1967. With sales of $115 billion, Koch Industries is the second largest private company in the US. He and his brother David own 84 percent of the company.

1) Larry Ellison – Net worth: 51.5 Billion

This 70 year old billionaire is the CEO of Oracle. He is also one of the company’s co-founders. On July 2 2009, for the fourth year in a row, Oracle’s board awarded 7 million stock options. Under his leadership, the company acquired Sun Microsystems.

The above-mentioned CEOs are well-known names in the world business community.