Quote from waggie945:
It is completely LEGAL to run in front of a commodity order if you purchase a contract month other than the one being purchased or sold.
ie.) Broker XYZ on the NYMEX has a 1500 lot order to purchase Feb. Crude. Local ABC "smells" the size and starts "lifting" every offer in March Crude. Totally legal.
Local ABC could legally buy Feb crude anyway, because it's not his customer/order, though, right? I thought that was primarily what locals do - jump in front of order flow.
Are you saying that Broker XYZ could lift those March offers for his own account, even though he knows that the arbs will run up February as soon as he does, yielding his customer inferior prices anyway? Not to mention that the addition of the arbitrage will probably create even more slippage for the original customer because of the need for the arbs to make a couple ticks in the process.