AGE: 42 OCCUPATION: Cofounder and chairman, Groupon; tech investor

If you listen to the skeptics, Groupon’s business is bound to slow; the deals are crummy; the stock is going nowhere. But let’s not forget that Lefkofsky and cofounders Andrew Mason (No. 11) and Brad Keywell (No. 21) pulled off the creation of a new global industry, not to mention 10,000 jobs and billions in wealth, which has benefited mostly Chicagoans. Lefkofsky edges out Mason because he lit the fire to start the company and, as of the November IPO, he was the largest shareholder—which gives him the ability to fund the blockbuster firms of the future.

MORE ON LEFKOFSKY: Groupon IPO: SEC May Tell Lefkofsky to Please Be Quiet, Please

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