6. Warren Buffett

Legendary American investor

Benjamin Wachenje
"You don't need to be a rocket scientist. Investing is not a game where the guy with the 160 IQ beats the guy with 130 IQ."

Chairman and CEO, Berkshire Hathaway
Born: Aug. 30, 1930, Omaha, Neb.
Education: Bachelor's in business administration, University of Nebraska Lincoln; master's in economics, Columbia Business School

There can be no more singular member of our list of the 25 leaders, icons and rebels of the past 25 years than Warren Buffett. He is widely regarded—revered wouldn't be too strong a word to the army of followers who hang on his every word—as the most successful investor of his era. Had you bought a share of his industrial holding company-cum-investment fund Berkshire Hathaway on the day CNBC launched in 1989, it would have cost you $5,875. Adjusted for dividends and splits, that share would be worth $185,000 today—more than five times the comparable gain in the S&P 500 over the same period.

Buffett is famous for his dry humor, plain living and folksy wisdom. Yet there is no disguising his razor sharp, disciplined mind and his uncommon acumen with numbers. If, as he wrote in his 2001 chairman's letter, "you only find out who is swimming naked when the tide goes out," Buffett would be the one left more fully clothed than a Victorian bathing belle.

Even after beginning to give away his fortune, his net worth is estimated by Bloomberg at $63.1 billion. For the year 2008, Buffett displaced his friend Bill Gates as the richest person in the world.

He has described himself as "85 percent Graham and 15 percent Fisher," referring to the authors of two of the sacred texts in the buy-and-hold value investing canon: Benjamin Graham's "The Intelligent Investor," which Buffett has called the best book ever written on investing, and Philip Fisher's "Common Stocks and Uncommon Profits." Graham and David Dodd, his co-author on the seminal "Security Analysis," taught Buffett at Columbia Business School in the late 1940s.

Buying undervalued companies with low overheads, high growth potential and a strong, defensible market share made Buffett a millionaire by 1960 and a billionaire by 1988. In 1991, already the largest shareholder in the Wall Street securities firm Salomon, he became chairman to steer it through a Treasuries bidding scandal that forced the resignation of John Gutfreund.

It was a preview of the white knight role he would play in the recession that followed the 2008 global financial crisis, when he put his money and reputation on the line to come to the aid of Goldman Sachs, General Electric and Swiss Re (he spurned Lehman Brothers).

Buffett now has a 21 percent interest in Berkshire Hathaway and has said it accounts for 98 percent of his net worth. Berkshire spans insurance (Geico), manufacturing (Clayton Homes), energy (MidAmerican Energy), services (NetJets) and transportation (Burlington Northern Santa Fe). It also owns stakes in a blue-chip roster of U.S. industrial and services companies—from American Express to Coca-Cola, IBM, Wells Fargo and Wal-Mart. He eschews businesses he doesn't understand, notably technology firms. "A pin lies in wait for every bubble," he has written. "And when the two eventually meet, a new wave of investors learns some very old lessons."

Warren Buffett: Lifelong highlights

  • Son of stockbroker and four-term libertarian Republican Rep. Howard Buffett
  • Bought his first stock at age 11: three preferred shares of Cities Service, a predecessor of Citgo
  • Fanatical bridge player; often plays with Bill Gates
  • Plays the ukulele
  • Announced in 2006 that he intended to give away 85 percent of his Berkshire holdings to five foundations in annual gifts of stock, with the largest contribution going to the Bill and Melinda Gates Foundation
  • Encourages the rich to take the Giving Pledge
  • Deducted $35 (for his bicycle) on his first tax return, filed when he was 13; deducted $23 million (for charitable gifts and local taxes) on his 2010 return
  • Met Charlie Munger in 1962, starting the long-term partnership between the two
  • Presides over Berkshire's annual shareholder meeting in Omaha, an event known as the "Woodstock of Capitalism"
  • Awarded the U.S. Presidential Medal of Freedom in 2011

Read MoreFULL LIST: CNBC FIRST 25

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