Perhaps someone will change my mind, but I see the block on insider trading and spoofing as harmful to the financial industry overall. Someone starts shorting a ton of Apple stock? That probably means something big is happen at Apple, and it's not good. It's information. Spoofing as a technique can be used to combat and inhibit other types of trading, and is in some sense an algorithm to 'keep the opponent honest'. A…
We should still discourage and ban it. Outside of what the market as a whole does, there's still the question of who benefits from it. Insider trading incentivizes some shitty behavior and some pretty major principle-agent problems.