GameStop sky-rocketed around 8,000% over six months. The stock became a piece in a rather complicated financial power struggle puzzle between a major hedge fund, Melvin Capital, and a group of internet investors who congregated on Reddit. GameStop became the subject of what's known as ' short selling ', a process in which professional investors borrow shares of stock to sell them and then buy them back at a later date, allowing them to make a profit if the stock price goes down. In simple terms, short-selling is a bet that the company will fail, with infinite loss potential.