Is Dan Loeb the Kanye West of Wall Street?

Billionaire hedge-fund manager Dan Loeb calls himself an “activist investor,” but even in the rough-and-tumble financial world, his tactics—nasty, personal attacks on C.E.O.’s and colleagues—are considered extreme. After nearly losing his Third Point fund, in 2008, Loeb has come roaring back, hunting such big game as Yahoo, Sony, Morgan Stanley, and Sotheby’s. From Wall Street to Hollywood, everyone is crying foul, but as William D. Cohan reports, Loeb’s ultimate weapon may be that he doesn’t give a damn.