IB allows bids at penny increments on options that trade at 5 ct increments on the exchanges. Also, spread orders are filled between the B/A without the quote going to that price (another party was doing the spread and your fill was part of it). I can't prove anything... I'm just suggesting that there are other possibilities for what you observed.Quote from hajimow:
I cannot prove it but I am 110% sure that it was not the case. The stock was flat for one hour and after I traded at 0.13 the bid/ask was still 0.1/0.15
