Pokemon GO conquered the world and sent Nintendo's stock surging into the stratosphere. Their stock price rose by over 50 percent, gaining over a billion dollars a day. It totaled over $10 billion in less than a week, and the pile of money might have hit the International Space Station if not for one small problem: Nintendo didn't actually make Pokemon GO. And Nintendo had to go out and tell everyone.
People bought 10-figure sums of shares until a presumably embarrassed Nintendo spokesperson publicly reminded everyone that the game is made by a different company. It's made by The Pokemon Company and Niantic, both of which are shown every time you start the game, with no sign of a comforting Nintendo logo in sight. Nintendo has only a 32 percent share in the whole thing and had already accounted for any possible profits in their previous projections.
The stock prices plummeted by more than 30 percent after people "discovered" a bit of news that a simple Google search or a play-through of the first two seconds of the game could have revealed. But people with longer memories than the stock market might notice this fall is less than the rise.