The leaders are just the current talkers. I say current because it's very, very likely that they're not the ones who originally formed anonymous. In fact I don't know if you could really say there ever was a founder. It's a stand-alone complex, to use the anime-term. A series of copycat events, yet no real origin of the copies. Look at the motives throughout the groups' history and nothing is consistent. There are no real "leaders." Just various people directing the masses when the chance arrives, claiming they're the original.
That's also why the FBI will never stop anonymous. It's not a group of people. It's not an organization. It's not a network. It's an idea.