Bill Gates continued his 18-year reign as the richest man in America's while the Berkshire Hathaway CEO Warren Buffet, the Kock brothers and heirs to the Walmart fortune rounded out the top ten of the Forbes 400, the magazine's annual list of the wealthiest Americans.

The people on the list represent a combined $1.53 trillion in value, a number that has risen 12 percent on the year since August 26. Young entrepeneurs like Facebook's Mark Zuckerberg continued to ascend the ranks while newcomers included LinkedIn's Reid Hoffman, Groupon's Eric Lefkofsky and Zynga's Mark Pincus.

Gates has held the title of America's wealthiest man since supplanting Buffet atop the hierarchy in 1993 -- the two men are now worth $59 billion and $39 billion, respectively. The entire top ten is below:

1. Bill Gates, Microsoft: $59B

2. Warren Buffet, Berkshire Hathaway: $39B

3. Larry Ellison, Oracle: $33B

4, 5. Charles Koch and David Koch, Koch Industries: $25B

6. Christy Walton , Walmart: $24.5B

7. George Soros, Hedge Fund Manager: $22B

8. Sheldon Adelson, Casino mogul: $21.5B

9. Jim Walton, Walmart, $21.1B

10. Alice Walton, Walmart, $20.9B