Here’s the briefest of explainers: after many years of steady decline, GameStop was not doing well and their stock was super low. Then, they hired some new board members and the stock went up. Institutional investors (aka hedge funds) observing the phenomenon decided to “short” GameStop stocks to make a lot of money when it failed. Then the /r/Wallstreetbets subreddit caught wind of their scheme and started buying GameStop stocks like crazy, hugely inflating the price of the stock so some hedge funds lost all their money.
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