AMC shares skyrocketed as much as 260% in premarket trading on Wednesday as day traders piled into heavily shorted stocks for a third consecutive day. From a report: Frenzied buying also drove GameStop shares up as much as 147%, BlackBerry up 31%, and Bed Bath & Beyond up 27%. Amateur investors have gathered, most notably on Reddit forum r/wallstreet bets, to pinpoint stocks they can buy en masse and score fast profits. They frequently target stocks that are popular shorts, as driving their stock prices up can pressure short-sellers into buying shares back to cover their positions, which sends prices even higher. Day traders also see the strategy as a way to stick it to Wall Street. They have targeted hedge funds such as Melvin Capital, which had negative positions in 17 US-listed stocks at the last count. Four of those – GameStop, Bed Bath & Beyond, Dillard’s, and Ligand Pharmaceuticals – jumped at least 10% in premarket trading on Wednesday.