The obvious suspicion, for any company that is both a market maker and doing prop trading, is that they're engaging in some sort of front running. They're prob

The obvious suspicion, for any company that is both a market maker and doing prop trading, is that they're engaging in some sort of front running. They're probably doing it in a highly obfuscated non-trivial way otherwise they'd get caught quickly, but nevertheless are using their visibility into trillions of dollars worth of order flow to shape their own trading strategy.