Nintendo shares have seen a stellar rise since the release of Pokemon Go, gaining more than 50%.
Shares shot up 16% on July 13, making an overall increase of 56% since trading closed on July 8 – the day the game became available.
Pokemon Go players search locations in the real world to find virtual Pokemon creatures on their smartphone screens.
The game has become a global phenomenon since its release.
Pokemon Go topped the app store download chart on both iPhone’s App Store and Google Play just days after its initial release in the US, Australia and New Zealand.
Nintendo shares had already started the week with a 25% jump on July 11 alone.
The Pokemon creatures first emerged in the 1990s on Nintendo’s Game Boy device.
For Pokemon Go, Nintendo has partnered with Niantic and the Pokemon Company, which owns the rights to the characters.
Nintendo, which is also behind the iconic Super Mario game, has traditionally relied on sales of its gaming consoles.
However, sales of those have been slowing in recent years as more gamers move online and onto portable devices.
Analysts have long criticized Nintendo for lagging its rivals like Sony and being late to the game in catering to the growing smartphone market.