Quote from fhl:
It seems to me you are making an assumption here about what he did, and then running with that assumption. What the trader said was "Everything showed that the order was canceled successfully an I did not get filled. By everything, I mean the order on the main window showed that it was canceled and then it went away, Book Trader showed that I had no position, and the account window showed that I had no position. " He didn't "forget about it" as you say. He said later he simply couldn't remember if he saw a red. That is quite different than just "forgetting about it", going away, and then being hit with the unexpected.
No, I don't think I am making an assumption. He should have made damned certain that he saw the red signal indicating successful cancellation, on every single cancellation request. If there was any doubt in his mind, about whether he saw red, he should have immediately called the trade desk. He did neither of these things. I think he was partly at fault for his own negligence.
I have also become convinced that IB is also partly at fault, for bad documentation leading to this problem. I come to this conclusion because it appears, from this thread discussion, almost unanimous that other IB traders are making the same mistake as this thread's original poster. If almost all of them are making this same mistake, it must be because IB's documentation did not adequately educate them as to procedures and responsibilities in regard to order cancellation requests. I appear to be one of the few exceptions because I am extremely cautious.
People, my advice is: DO NOT RELY ON DISAPPEARANCE OF AN ORDER, FROM TWS, TO SIGNAL IT WAS CANCELLED. The official database of submitted orders is held on IB's servers, not your own computer. An order can disappear from your TWS, even though it has not been cancelled, and IB servers show that it is working or already executed. It is unwise to rely upon the absence of something to confirm an order cancellation. Far wiser to rely on the presence of something, an affirmative, deliberate, electronic signal (the red code on your TWS screen), or IB's verbal assurance that you are confirmed out.
You guys are playing Russian Roulette. If you cancel hundreds or even thousands of orders a day, and only a few of them fill because you falsely assumed they were cancelled after they disappeared from your TWS, your entire account could be wiped out by the time you discover the executions, which might not occur until days later. Please, people, look for that red signal. Slow down and stop taking these chances. Do not ever consider an order cancelled until you either see the red signal, or IB verbally tells you it is cancelled.