Quote from logic_man:
OK, so let's run through the math on trying to steal an edge from a small trader. Let's say I know that 90% of small traders are going to lose. That means only 10% of the small traders who trade through me have anything worth stealing in the first place (maybe that percentage goes up a bit if I were to steal their strategy and implement it with my own cost of trading structure). On the flip side, I know that the traders I hire to trade my capital have a 50% success rate, once they get through my hiring process, since I only hire 1 out of every 100 people who apply, making sure I get the best people I can.
So, why would I go through all of the trouble of setting up the infrastructure to monitor and reverse engineer small traders' accounts and strategies, especially since I don't know in advance which 10% of my small traders will be successful, so I have to track every single one of them, when I could spend that money interviewing and hiring my own traders? How in the world would a person who brought that idea up to the CEO be able to convince the CEO to go along? If I were the CEO of a brokerage firm and someone brought this idea to me, I would fire them. Not because I'm some highly-ethical guy, but because it is a stupid idea, with almost no payoff and huge risk.
As for "grey areas" in the law, when has that ever stopped class action lawyers before? The amount of money they could make successfully prosecuting a broker who did this would absolutely give them an incentive to find cases.