TOKYO - For Nintendo, "Pokemon Go" just keeps on giving.
Shares in the Japanese game maker closed up 14 percent at 31,700 yen ($300) in heavy trading Tuesday on the Tokyo Stock exchange, more than twice where they stood when the wildly popular augmented-reality game was launched on July 6.
Nintendo accounted for nearly one in four shares that changed hands on the TSE's main board. The sharp rise has doubled the Kyoto-based company's market capitalization to 4.5 trillion yen ($42.4 billion).
"Pokemon Go," a smartphone app that uses Google Maps to overlay reality with Pokemon creatures, was developed by Niantic, a Google spinoff that Nintendo Co. invested in last year. The game has yet to be released in Japan and the rest of Asia.