Nintendo's stock drops as investors learn it didn't create Pokemon Go

Nintendo's stock value has reversed course today and begun a rapid descent following the company's message to investors last Friday that the remarkable success of Niantic and The Pokemon Company's mobile game Pokemon Go likely won't have much effect on Nintendo's bottom line.

This is worth pointing out because it's a good example of how uninformed or overly optimistic sentiment among investors can cause the stock values of publicly-traded companies like Nintendo or Sony to undergo radical short-term shifts.

While Gamasutra occasionally reports on changes in the financial markets if they seem like something game developers would be interested in, such shifts should always be taken with a grain of salt.

Last week, Nintendo surpassed Sony in terms of market value thanks to the success of Pokemon Go, even as at least one financial analyst warned that it would be difficult for the company to maintain that value. 

Today, following Nintendo's reminder to investors that it does not receive a direct cut of the revenue generated by Pokemon Go, Bloomberg reports that the company's stock value has dropped by as much as 18 percent (see chart below) and it seems likely that descent will continue.