Howard Lutnick has tightened his grip and owns about 60% of Cantor Fitzgerald.
Jeff Green set out to create the Goldman Sachs of online advertising.
America's richest people see their wealth continue to soar despite their hefty charitable gifts.
The Affordable Care Act brought insurers millions of new customers.
When Jeff Bezos gambled on starting his online bookstore in 1995, his parents gave him a check for $245,573.
His net worth has soared by $52 billion this year.
Self-made wealth is surpassing royalty among the list of wealthiest people in the U.K.
More billionaires may be on the way as the money manager spreads its ownership among a wider pool of employees.
The recovery in Facebook shares has rewarded other insiders as well.
Winfrey, 64, can largely thank the performance of Weight Watchers International.