40 Under 40

by Fortune staff
Thursday, October 20, 2011

They're the hottest young stars in business across the globe. They're innovators, disrupters, and job creators; in fact, it's a pretty safe bet you're going to be working for them someday — if you aren't already! They're in technology, yes, but also in movies, music, athletic wear, and even curry-flavored chocolate. And the scary thing is they're just getting started.
1. Mark Zuckerberg

Photo: David Yellen

Founder and CEO, Facebook
Age: 27
Industry: Technology
This may have been the year your grandmother joined Facebook. The Harvard dropout and tech wizard is a household name, thanks in part to The Social Network, but the real-life script is still being written. In 2011 his baby hit 800 million users and was valued at $50 billion, setting the stage for a monster IPO to come. The company also partnered with Skype and redesigned key parts of its service, leading to the usual temporary backlash.
On the hunt: Zuck made headlines earlier this year when he told Fortune his goal for 2011 was to eat only animals he had personally killed.
2. Larry Page

Courtesy: Google

Co-founder and CEO, Google
Age: 38
Industry: Technology
Since retaking the reins at Google last April, the introverted Page has won praise for making some fast decisions — and big acquisitions. He's cut back on nonessential projects, while plowing resources into Facebook competitor Google. Ad-driven revenue is stronger than ever — in July the company reported record-breaking quarterly earnings. But with nearly 30,000 employees across some 30 countries, steering the search giant back to its nimbler roots won't be easy. Even Page recently admitted Google's biggest threat is, well, Google.
Net worth: Page is now worth some $17 billion.
3. Greg Jensen

Courtesy: Bridgewater

Co-CEO and co-CIO, Bridgewater Associates
Age: 37
Industry: Finance
Jensen's work overseeing research at the world's largest hedge fund (assets under management: $125 billion) has paid off. Bridgewater's flagship fund is up 25%, while many marquee names are losing money. Jensen also oversaw the rollout of the $10 billion fund Pure Alpha Major Markets in June. Jensen, who started at Bridgewater as an intern while at Dartmouth, believes the firm's unusual culture (articulated by founder Ray Dalio in the form of 300 self-help principles) is the key to the firm's success — and his own.

4. Aditya Mittal

Courtesy: ArcelorMittal

CFO, ArcelorMittal
Age: 35
Industry: Industrial
He's more than just the son of his company's billionaire founder: The finance whiz helped build the world's biggest steel group through acquisitions — and is now helping run it. This year he assumed responsibility for European operations, the company's largest division, and he just returned from the Arctic, where the company's new iron ore mine is one of billions of dollars' worth of new projects.
Media diet: He reads the state-controlled China Daily every day "to get perspective on how they are framing the news."
5. John Arnold

Photo: Centaurus Advisors

Founder, Centaurus Energy
Age: 37
Industry: Finance
The trading star who cut his teeth at Enron turned a talent for reading the notoriously fickle gas markets into an estimated $4 billion hedge fund fortune. He's bounced back from his first-ever down year, with his flagship fund up about 4%, and invests in natural-gas storage caverns and power plants, turning Centaurus into a diversified energy firm some have likened to a mini-Enron. Billionaire props include an art-filled modernist mansion in Houston and a foundation to support overhauling America's pension system.
Spare time: Arnold is said to be a Dave Matthews and U2 fan.
6. Brian Deese

Courtesy: National Economic Council

Deputy director, National Economic Council
Age: 33
Industry: Government
A driving force behind the auto bailouts, the Obama administration's most unalloyed win to date, Deese cemented his wunderkind status on the White House economic team by building the case against liquidating Chrysler. Now the Yale Law graduate claims an even bigger portfolio — ranging from Wall Street reform to housing finance — and the President's full attention. When Obama decamped for Martha's Vineyard in August, Deese went along to help him craft his new jobs plan.
Linguistic pet peeve: When people confuse "further" and "farther." ("Don't know why, but it drives me nuts.")
7. Daniel Ammann

Courtesy: General Motors

CFO, General Motors
Age: 39
Industry: Automotive
Last fall Ammann spent weeks on the road persuading investors to buy General Motors stock. Now he's working to keep them happy. The native New Zealander advised GM for years as a Morgan Stanley banker before taking over as CFO this spring. His job today: making sure the automaker stays profitable in any market — historically a tough task for GM. "We're off to a good start," says Ammann, who splits his time between Detroit and New York City; this year GM has earned $6.3 billion in a humdrum economy.
Least favorite business term: "End-to-end solution."
8. Jack Dorsey


Co-founder and executive chairman, Twitter; co-founder and CEO, Square
Age: 34
Industry: Technology
Dorsey's comeback is a classic Valley tale: After being ousted as CEO of Twitter in 2008, he returned to the company he helped found to lead product development (and clean house — four of Twitter's key product execs reportedly left in July). He continues to run Square, his hyper-hot mobile-payments startup, which has shipped more than 800,000 of its credit card readers and recently closed a $100 million round of funding, giving it a valuation north of $1 billion.
Relaxation technique: Dorsey is a big fan of going for walks; he also takes "microvacations," driving on Sundays to nearby Point Reyes or Big Sur.
9. Jeff George

Courtesy: Sandoz

Global head of Sandoz, Novartis
Age: 38
Industry: Consumer Products
Since joining Novartis in 2007, George, a former international-relations student and McKinsey consultant, has shot up the ranks at the Swiss pharmaceuticals giant. After stints in the company's vaccine and emerging-markets divisions, he was tapped in 2008 to lead Sandoz, the company's massive generics unit, whose $8.5 billion in revenue makes it the world's second-biggest generics operation after Israel's Teva. With George at the helm, Sandoz has posted double-digit revenue growth and made big gains in the field of biosimilars, or generic versions of complex drugs.
Stress reliever: Meditates each morning and runs three to four times a week.
10. Sid Sankaran

Courtesy: AIG

Chief risk officer, AIG
Age: 34
Industry: Finance
The financial crisis proved that AIG had no clothes — or at least no controls. Now it's up to Sankaran, a Canadian math hotshot (his degree from the University of Waterloo was in actuarial sciences) and former partner at consultancy Oliver Wyman, to make sure it doesn't happen again. Sankaran declined AIG at first; today, as chief risk officer, he oversees the billions flowing among disparate insurance operations and reports to CEO Robert Benmosche if something suspicious rears its head.
—Editorial package reported by Katie Benner, Scott Cendrowski, Betsy Feldman, Mina Kimes, Alex Konrad, Beth Kowitt, Collen Leahey, Michal Lev-Ram, Tara Moore, Tory Newmyer, Daniel Roberts, Christopher Tkaczyk and Anne Vandermey.