I have a really bad experience recently. My broker filled my market order 1 minute 11 seconds after I clicked to buy. Initially when after I clicked the price, the market moved in my favor, the broker didn't execute the market order and after 1 min 11 seconds, when the market reversed strongly they executed the trade resulting in an instantaneous loss of 60 pips! My question is can they hold my market order indefinitely and fill it when they have the opportunity to rip me off?