I think what the academic world doesn't understand about trading is that even if a piece of information is freely available you need an expert eye to interpret it. The trader doesn't have to act break a law to get indications of a large buyer on a stock, or a large seller, or to notice patterns. Nor does he need to to break the law in order to figure out a way to provide liquidity in a profitable fashion. It's a matter of skill and hard work. This skill is so hard to master that even the best traders still loose a lot of money and are frequently wrong. They just make enough money when they're right to be profitable in the end. The same is true of long term investors, but on a grander scale. When they're winning you hear about it in the Wall Street Journal. Same thing when they loose. Hedge funds are an example of this. To these funds the managing traders charge a huge percentage of profits. As a result the net return investors get is not always impressive. That doesn't change the fact that money is being made on the market. Academics don't even realize that in a way they are disproving their own hypothesis when they talk so strongly about EMH. They are proving that insufficient market participants are common while demonstrating how easy it is for very smart people to be ignorant of the fact. As for proof it's possible to make consistent money on The Market? Look at the paychecks good of traders and investors everywhere. These guys are paid by percentage. When you subtract that percentage from the returns they generate the resulting amount is not always impressive. The people who put up cash for these operations just wants a good return on their money. They have no market skills. So they pay traders a huge premium to supply a return that might just beat the market in the long run. How can traders charge such incredible prices? Because if they weren't making a sweet cut of what they were generating for someone else they would just quit and trade their own account. This option exists for any good trader. It drives the prices for their services to the moon. Money can be made off the market. Those that can do it are very wealthy. For the rest there's Efficient Market Hypothesis.