RenTech is also basically the only largest hedge fund that has beat the market by a wide margin for decades. An average 66% annual return in their Medallion Fund since 1988 according to wikipedia. That is pretty much insane and seems to be something only space aliens could do. If anyone is using quantum computers to help trade, it is probably them.
Medallion is also kept very small because I would guess the tricks that they use to keep those returns so high (maybe even some sort of topological quantum field theory!) don't scale well to larger investments.
Not sure if I would call ~$10 billion very small and making $6-7 billion per year is good chunk of money. But, yea, I'm sure that would get bigger if they thought they could keep their returns high.
That's because it's not 66% but instead $6B. If they had twice as much capital it would be 33%, and if they had ten times as much capital it would be 6.6%. I'm simplifying to show the main point.
