10. James Simons
Net worth: $14.3 billion
Age: 77
Country: US
Industry: Hedge funds
Source of wealth: Self-made; Renaissance Technologies
Before revolutionizing the hedge fund industry with his mathematics-based approach, "Quant King" James Simons worked as a code breaker for the US Department of Defense during the Vietnam War, but was fired after criticizing the war in the press. He chaired the math department at Stony Brook University for a decade until leaving in 1978 to start a quantitative-trading firm. That firm, now called Renaissance Technologies, has more than $65 billion in assets under management among its many funds.
Simons has always dreamed big. About 10 years ago, he announced that he was starting a fund that he claimed would be able to handle $100 billion, about 10% of all assets managed by hedge funds at the time. That fund, Renaissance Institutional Equities Fund, never quite reached his aspirations — it currently handles about $10.5 billion — but his flagship Medallion fund is among the best-performing ever: It has generated a nearly 80% annualized return before fees since its inception in 1988.
In October, Renaissance shut down a $1 billion fund — one of its smaller ones — "due to a lack of investor interest." The firm's other funds, however, have been up and climbing. Simons retired in 2009, but remains chairman of the company.
9. Ray Dalio
Net worth: $16.3 billion
Age: 66
Country: US
Industry: Hedge funds
Source of wealth: Self-made; Bridgewater Associates
Ray Dalio's hedge fund, Bridgewater Associates, is the biggest in the world, managing a portfolio of around $154 billion in global investments.
At the top of his industry and having amassed an enormous fortune, Dalio has more recently focused on giving away money and advice. He's taken the Giving Pledge, committing to donate the majority of his wealth to charity. And last year he shared his highly coveted "investment secrets," albeit in an unorthodox manner for a hedge funder, in a 30-minute YouTube video, which has been watched more than 2 million times. His 123-page, self-published manual on his principles of money management and leadership is also seen as somewhat of a bible among the investment world.
Dalio has always taken a radical approach to management, making everything he and his fund does completely transparent to employees. And it's worked well for him: Bridgewater, while sometimes viewed as "cultish," is one of the most coveted places to work in finance. Dalio has said that he attributes his success, in part, to reminding himself that history repeats itself and keeping track of the decisions he's made that didn't work.
8. Len Blavatnik
Net worth: $16.7 billion
Age: 58
Country: US
Industry: Diversified investments
Source of wealth: Self-made; Access Industries
After earning degrees at Columbia University and Harvard Business School, Len Blavatnik — a Ukraine-born American — founded Access Industries, a privately held industrial company, in 1986. The company began with only Russian investments, but it now boasts a diverse portfolio that includes natural resources, chemicals, media and telecommunications, and real estate.
Blavatnik built his fortune through business savvy and a knack for making well-timed investments. In 2004, his company purchased a 20% stake in Tory Burch, becoming the first and largest outside investor in the fashion house, which has since blossomed into a powerhouse retailer worth over $3 billion. He's credited with one of the greatest investments of all time in his risky buyout of petrochemicals maker LyondellBasell, which he purchased out of bankruptcy amid the financial crisis for north of $2 billion. The value of his stake had jumped to more than $10 billion in 2014. He incurred a comparatively measly fine of $656,000 from the Federal Trade Commission in October for failing to properly report his investments in the company.
Recently he's tried his hand as a music mogul, purchasing Warner Music Group in 2011 for $3.3 billion. Two years later, he bought British label Parlophone for $742 million, giving him an expanded roster of musical acts that includes Coldplay, Blur, Metallica, and Bruno Mars. His music holdings also include investments in emerging-technology companies such as Spotify and Beats Electronics.
7. Carl Icahn
Net worth: $18.7 billion
Age: 79
Country: US
Industry: Diversified investments
Source of wealth: Self-made; Icahn Enterprises
Carl Icahn has made a lifelong habit and lucrative career out of agitating undervalued and poorly managed companies to change their ways. Since founding his own investment firm in 1968, Icahn has become one of the most powerful people in finance, investing in scores of high-profile companies, including RJR Nabisco, Philips Petroleum, Viacom, Marvel, Time Warner, Netflix, and Herbalife.
And he usually gets his way. When Icahn revealed that he held a stake in Apple worth more than $1 billion in 2013, the company's stock shot up and CEO Tim Cook responded to Icahn's critique of the company. Cook has even come around to some of Icahn's views, and Icahn said in the fall that he may buy an even larger stake.
Now Icahn's leading the charge against AIG, publishing an open letter in January calling for the insurance giant to break up into a "smaller, simpler company."
Icahn has said that he has no plans of retiring from pestering corporate executives, but a career shift may nonetheless be in the works. Donald Trump has said that if elected US president, he would bring Icahn in as Treasury secretary — a position which Icahn said he would accept despite some disagreements with the combative real-estate mogul's positions.
6. Li Ka-shing
Net worth: $19.5 billion
Age: 87
Country: Hong Kong
Industry: Diversified investments
Source of wealth: Self-made; CK Hutchison Holdings
Despite humble beginnings, business magnate Li Ka-shing has become the wealthiest man in Hong Kong. After his father died of tuberculosis, Li dropped out of school at 16 to support his family, working in a factory making plastic flowers. Six years later, he opened his own factory, the predecessor to what's known today as CK Hutchison Holdings, a vast business empire with interests in real estate, manufacturing, energy, telecommunications, and technology. A savvy investor, Li and his venture-capital fund Horizon Ventures have backed companies like Facebook, Skype, Spotify, and the egg-replacement food startup Hampton Creek.
Last year Li reorganized his business affairs under two new listed companies, one entity for property holdings and another for all other global assets. The move is most likely in preparation to hand over control of his sprawling fortune to his son, but the 87-year-old doesn't have any plans of slowing down just yet. In August, he opened the 12,000th location of AS Watson, CK Hutchison's health and beauty-products retailer, now the largest in the world.
5. George Soros
Net worth: $21.7 billion
Age: 85
Country: US
Industry: Hedge funds
Source of wealth: Self-made; Soros Fund Management
Born in Budapest, George Soros lived through the Nazi occupation of Hungary during WWII before fleeing to the UK and later settling in the US. Touted as "the man who broke the bank of England," he's best known for the Quantum Fund, a hedge fund he launched in 1973 under his Soros Fund Management company. In 1992 he shorted the British pound, a risky move that ended up earning the fund $1 billion in a single day and solidifying Soros' place in the finance world. Quantum Fund also generated annual returns over 30% under Soros' leadership, making it one of the most successful hedge funds of all time.
Today, Soros remains chairman of Soros Fund Management, which manages more than $25 billion in assets, including stakes in prominent companies like Amazon, Facebook, and Netflix. He's also chairman of Open Society, an organization he founded in 1979 that operates as a network of foundations and partners across the globe that promote the values of open society and human rights.
Soros is actively interested in politics as well, seen as a friend to liberals and an enemy of conservatives in the US. He donated $2 million to super PACs supporting Hillary Clinton last year, and warned against the "siren songs" of Donald Trump and Ted Cruz in a recent op-ed for The Guardian.
4. Alwaleed bin Talal bin Abdul Aziz al Saud
Net worth: $22.5 billion
Age: 60
Country: Saudi Arabia
Industry: Diversified investments
Source of wealth: Inheritance/self-made; Kingdom Holding Company
Prince Alwaleed — grandson of Abdul Aziz al Saud, the first ruler of the Kingdom of Saudi Arabia — built his fortune with savvy investments in a range of companies across the US and the Middle East. He founded Kingdom Holding Co. in 1980 and has since invested in everything from real estate to entertainment to education, with stakes in companies like Twitter, The Four Seasons, Time Warner, and Motorola.
Recently, Prince Alwaleed also made a play for ride-hailing service Lyft, reportedly grabbing a 2.3% stake by putting up $105 million of a nearly $250 million round of funding the company raised in December.
Prince Alwaleed has an enigmatic relationship with his money. In 2013, he sued Forbes for allegedly underestimating his wealth. But last summer he announced plans to donate his entire fortune to charity anyway.
3. Jorge Lemann
Net worth: $25 billion
Age: 76
Country: Brazil
Industry: Diversified investments
Source of wealth: Self-made; 3G Capital
Once dubbed "the world's most interesting billionaire" by Bloomberg, Jorge Lemann had previous lives as a journalist and professional tennis champion before turning to finance in 1971 with the purchase of a small Brazilian brokerage firm. He later went on to cofound investment company 3G Capital in 2004, through which Lemann has become best known for his affinity for mergers and acquisitions — especially with frequent deal partner Warren Buffett.
At the end of 2014, Lemann created a fast-food giant, with the help of Buffett's Berkshire Hathaway, by merging Burger King with Canadian brand Tim Hortons in a series of deals worth over $11 billion. Then last March, 3G and Berkshire Hathaway teamed up again to invest $10 billion into the megamerger of Kraft and Heinz, which created the fifth-largest food and beverage company in the world with combined revenues of $28 billion.
And in November, 3G's Anheuser-Busch InBev orchestrated a mammoth $108 billion deal to take over SABMiller, becoming the most dominant beer producer in the world. The megamerger puts brand-name beers like Budweiser, Stella Artois, and Leffe all under one roof, and it puts Lemann one step closer to his lifelong dream of controlling the beer market.
2. Michael Bloomberg
Net worth: $42.1 billion
Age: 73
Country: US
Industry: Financial services
Source of wealth: Self-made; Bloomberg LP
Michael Bloomberg founded his financial-data firm in 1981 following a lucrative career at investment bank Salomon Brothers, which he joined in 1966 after earning his MBA from Harvard Business School. He added a news and media subsidiary to his company in 1990, but even today the bulk of Bloomberg LP's $9 billion in revenues still comes from the sale of terminals that Wall Street traders rely on for the most up-to-date financial and market information.
He left the company to run New York City as mayor in 2002 and served three terms. But rather than spend his time after leaving office in 2013 by giving away his immense wealth, as expected, he instead returned to Bloomberg LP to overhaul the newsroom and take the company in a new direction.
Now, Bloomberg may be looking to return to public office. He is reportedly exploring the possibility of an independent presidential bid. Though he faces an uphill battle — he's a pro-business fiscal conservative who also supports gun control, abortion rights, and efforts to curb climate change — his personal war chest will come in handy. The former mayor, who spent $261 million on his campaigns for New York City office, says he'd spend as much as $1 billion of his own money on a presidential run.
1. Warren Buffett
Net worth: $60.7 billion
Age: 85
Country: US
Industry: Diversified investments
Source of wealth: Self-made; Berkshire Hathaway
Berkshire Hathaway CEO Warren Buffett started his prodigious investing career at a young age. As a child he delivered newspapers on his bike, and by 11 the precocious Nebraska native had purchased his first shares in the stock market — Cities Service Preferred at $38 apiece — and sold them for a $5 profit. He was rejected from Harvard Business School, so Buffett went to Columbia Business School instead and learned under iconic value investor Benjamin Graham, who would become a mentor to the budding financier. Buffett worked as a securities analyst in the early-1950s before starting his own investment firm. He bought textile company Berkshire Hathaway in 1969, transforming it into a holding company that would house the many lucrative investments that helped build his massive fortune and earn the nickname "The Oracle of Omaha."
The array of portfolio companies and investments that made him rich may appear random — he's bet on companies including Coca-Cola, American Express, Geico, Fruit of the Loom, Dairy Queen, and General Motors — but they're all cash-generating machines that offer long-term value. In August he announced his largest acquisition ever: a $37.2 billion buyout of nuts and bolts maker Precision Castparts.
A frugal man with a fondness for junk food, perhaps the most impressive part of Buffett's $60 billion fortune is that it doesn't include the $21.5 billion he's already given away. He's good friends with Microsoft cofounder Bill Gates, whom he collaborated with to create the Giving Pledge, a promise for billionaires to give away at least half of their wealth to charity.