I've been trading 1-lots in EuroStoxx50 for a couple of days, as I'm preparing to make a transition into that market from equities (so far going well). I am however wondering about the sometimes sizable trades going on the bid/ask which doesn't seem to be volume lifted from the order book. I know Eurex has a function for doing block trades, but I'm wondering if this volume is for real or if it's just trades messaged into the exchange with the intent of screwing up volume charts and changing market perception. Anyone?