GameStop shares slump as Reddit rally ebbs

(Reuters) - Shares of videogame retailer GameStop Corp slumped on Monday, losing ground along with a slew of other social media-hyped stocks that took investors on a wild ride earlier this month. GameStop and other "meme stocks," including cinema operator AMC Entertainment Holdings Inc and headphone maker Koss have seen wild gyrations in their share prices over the past two weeks as amateur investors on forums such as Reddit's WallStreetBets acted in concert to bid up stocks that some U.S. funds had bet against. The volatility has drawn the attention of regulators, although U.S. Treasury Secre...