It was once a closely guarded mystery to the citizens of Gotham City and beyond, but these days the list of people who know Batman’s secret identity is getting pretty long. That’s partly due to Bruce Wayne’s ever-expanding cadre of allies, even outside of the Bat-Family, but the also-expanding amount of villains who know Batman’s true identity is pretty troubling. It’s hard to keep a secret for nearly a hundred years of published history, it seems, and now dozens of Gotham’s best and worst are in on it.
Some of Batman’s worst enemies know he’s Bruce Wayne under that mask, and so do a long list of current and former Bat-lovers. DC Comics’ continuity has rebooted a couple of times over the decades, but the Dark Knight’s personal history has remained fairly consistent through it all - including the not-so-secret nature of his alter ego.