In the summer of 2008, Michael Bloomberg made a truly artful deal. In a $4.4 billion deal that included only $110 million in cash, the then-New York City mayor purchased Merrill Lynch’s 20 percent share of his media company Bloomberg, LP. The transaction bumped Bloomberg’s estimated individual net worth from $11.5 billion to over $15 billion.

That’s a handsome sum. According to Fortune, the media mogul mayor had “pickpocketed” one of Wall Street’s most venerable investment houses. As suggested by Merrill’s ownership of such a large stake, Mike Bloomberg was also taking money from an old friend.

Amid the meltdown of 2008, Bloomberg’s longtime business partner, often referred to as “Mother Merrill,” had fallen on hard times. Spurred by its hard-charging ex-CEO, Stanley O’Neal, the formerly cautious investment house lost big betting on risky bundles of subprime mortgages. But now the mayor who had fought off regulation of predatory lending during his first term cashed in. Call it the Wall Street version of the American Dream.