Based on The Forbes 400: The Richest People in America, Bill Gates, philanthropist and Microsoft Corporation (NASDAQ:MSFT) founder, and Warren Buffett, chairman of Berkshire Hathaway Inc. (NYSE:BRK.A) (NYSE:BRK.B), remained the richest Americans.

Warren Buffett and Bill gates

Gates is the richest American, with a $66 billion net worth. He is considered one of the world’s most generous persons, as he has donated $28 billion so far in various charitable programs, including funding researches for vaccines for AIDS, malaria, meningitis, pneumonia, and other deadly diseases. His latest project is to build better toilets for people without water or sewage systems.

Warren Buffett is the second richest American, with a $46 billion net worth. In April, he was diagnosed with prostate cancer, but he assured the shareholders Berkshire Hathaway that his condition is not life threatening. He completed his 44 cycles of radiation therapy this month. According to Forbes, Buffett’s charitable contribution is worth $17.25 billion. In July, he donated $1.5 billion to the Bill & Melinda Gates Foundation.

Larry Ellison, co-founder and CEO of Oracle Corporation (NASDAQ:ORCL) is the third richest man in America, with a $41 billion net worth. Ellison owns 98 percent of Lanai, an island in Hawaii. He joined the Gates-Buffett giving pledge in 2010 and so far, has donated $445 million in Oracle stock through the Ellison Medical Foundation that supports research on aging and age-related diseases.

Charles Koch, chairman of Koch Industries, is the fourth wealthiest man in America along with his brother David Koch. The Koch brothers have $31 billion net worth each. Charles donates more than $40 million every year to his foundation to provide grants to colleges and universities, to study “market-based tools that enable individuals, institutions, and societies to prosper. ” He also provides funding for groups engaged in raising next-generation free-market entrepreneurs. David serves as vice chairman of Koch Industries. He supports the “moonshot” campaign to find a cure for cancer, and has donated $250 million.

The next wealthiest American is Christy Walton & family, with a $27.9 billion net worth.  She is the widow of John Walton, the son of Wal-Mart Stores, Inc. (NYSE:WMT) founder Sam Walton.  She is the co-chairman of the Children’s Scholarship Fund.

Other notable rich Americans include:

  • Jeff  Bezoz, founder and CEO of, Inc. (NASDAQ:AMZN), with a $23.2 billion net worth. Bezoz is the 11th wealthiest American
  • Sergey Brin and Larry Page, co-founders of search engine giant Google Inc (NASDAQ:GOOG) both ranked as the 13th richest Americans with $20.3 billion net worth each.
  • George Soros is the 15th richest American, with $19 billion net worth. He is considered as one of the world’s greatest money managers. He is also popularly known as “The Man Who Broke the Bank of England”, after speculating that the pound sterling was overvalued. He retired last year and turned his hedge fund into a family office, returning just under $1 billion in assets to outside investors.
  • Carl Icahn is the 21st richest man in America. The activist investor has a net worth of $14.8 billion. He is known for shaking-up the board corporations, wherein he has large investments. Most recently, he criticized Navistar International Corp (NYSE:NAV) and demanded four board seats. He threatened a proxy-fight with the management of the company, if they refuse cooperate in resolving the issues he raised against the company.
  • Mark Zuckerberg was listed as the 36th richest man in America, with $9.4 billion net worth. The Facebook Inc (NASDAQ:FB) founder suffered major challenges related to the company’s IPO. His net worth fell more than $8.1 billion after Facebook Inc (NASDAQ:FB)’s stock value declined from $38 per share offering price, to as low as $17.55 per share. During his latest interview, he impressed analysts and investors with his message, and helped the stock to go up. Facebook’s stock value is around $23.30 per share, up by more than 6 percent on Wednesday, in afternoon trading.
  • David Einhorn, CEO of Greenlight Capital, is now worth $1.3 billion
  • Daniel Loeb, CEO of Third Point, is also worth approximately $1.3 billion
  • Leon Cooperman, CEO of Omega Advisors, is worth $2.2 billion
  • Despite the woes of Sears Holdings Corporation (NASDAQ:SHLD), Eddie Lampert is worth $3.2 billion
  • David Tepper, of Appaloosa Management, is worth approximately $5.5 billion
  • Ray Dalio, the rising star in the hedge fund world, is worth $10 billion
  • Despite the recent poor performance of his hedge fund, John Paulson is worth $11 billion

Forbes estimated that the combined net worth of the 2012 class of 400 richest Americans is $1.7 trillion, higher than the $1.5 trillion estimate in 2011.  Ellison recorded the highest gain  ($8 billion) in 2012.  Forbes started ranking the wealthiest persons in America in 1982.