Earlier this year, Nintendo announced a partnership with DeNA to create and release five mobile games by March 2017. The first of these games was slated to launch this year, and Nintendo's stock skyrocketed with the announcement. During Nintendo's second quarter investor briefing, the first mobile game, Miitomo, was announced, and Nintendo President Tatsumi Kimishima also announced that its release has been delayed until March 2016.
Just as quickly as Nintendo's stock shot up, it has come crashing down. Immediately after the delay was announced, Nintendo's stock sank by 10%, costing them billions in market value. Since then, it has stabilized slightly, but it's currently down over 8%. Additionally, DeNA's stock has dropped an astounding 15%, and it's still falling as this is being written.