Trewsa - discovered today that Squaregain had excecuted a 50p stop-loss on Tanfield at 12.40pm on 22nd Dec (i.e after market close). I checked the sales data and the spread was approx 54.25-55p at that time. Being relativey new to te game (but loving it), I rung them to find out what the hell was happening. Apparently, they inform me that an MM had left this computer on after close and it triggered shed-loads of open stop-loss orders. They immediately replaced my stock volume of shares. Having said all this, I will take on board some of the good advice above regarding the use of close stops on sub 100p shares. Makes sense to me.