Yasuhide Kobayashi, Senior Vice President of Sony's Japan Studio, revealed internal research from Sony breaking down the estimates of revenues other Japanese publishers take from their home market. Their figures have it that Koei gets 91.8 percent of its sales from Japan, followed by Tecmo with 89.6 percent and Square Enix at 86.6 percent. Japan Studio of Sony pulls 66.9 percent, which is still outpaced by Konami (74.8 percent) and Namco Bandai (76.8 percent.)

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http://kotaku.com/5362014/sony-japan-studio-chief-we-have-to-develop-the-global-title