Yu gotcha

By selling evildoers short from the Bat Cave (where was he when Bernie Madoff was flying high?);

The company was founded by Daniel Yu, a Massachusetts Institute of Technology graduate and former hedge-fund analyst, according to people who know him.In an email, Mr. Yu declined to disclose the firm's size, how it makes money or provide details about himself. One of the few areas on which he was willing to elaborate was Gotham's history, saying the firm got its start when he and some others lost money investing in companies that were deceitful or committed fraud.

"We were victims of these corporate fraudsters. We believed this isn't right, and that the world needs someone to expose these crooks," Mr. Yu wrote. "And so, just as Batman catches criminals (and then submits them to authorities) using little more than his wit and some nice gadgets, Gotham City Research was born."

When Yu gets you, babe, you stay got;

Mr. Yu wrote that Gotham had spent eight months working on Gowex. He wouldn't say how much Gotham had made off its call, saying it was "dwarfed" by Mr. Garcia's "cumulative profits earned by defrauding [Gowex's] investors."

"Daniel's achievement here wasn't just identifying fraud, it was the meticulous documentation to the point where Gowex had no chance" of recovering, said hedge-fund manager John Hempton, of Australian firm Bronte Capital, who is friendly with Mr. Yu. "That's no small achievement."

Private law enforcement steps in where regulators fear to tread.