[flattone]

Youre saying at some point big HF will say 'a bunch of robin money is in some stock(s)' and make a move to cause losses for the RH folks?

>It has happened before in history

When?

[mlyle]

Big HF will see event requiring lots of RH people to pull liquidity, and know what equities this will move, and move first.

Not to mention that big HFT uses order book data from retail to vacuum away pennies on every transaction.