When Sega acquired Index Corporation, the parent company of Atlus, the deal was done under a new subsidiary called Sega Dream Corporation. Instead of using that company name, they’re changing the name of Sega Dream Corporation to… Index Corporation. So, basically Index Corporation is just a subsidiary of Sega Sammy instead of it being part of Sega Dream Corporation.
The more important question is who is in charge of Index Corporation now that it’s integrated into Sega? Sega Sammy Chief Operating Officer Naoya Tsurumi is now the president of Index Corporation and Yasuhiko Hamada is the Executive Vice President.
Yukimasa Murakami, the Managing Director of Index Corporation before the acquisition, is still the managing director of the new Index Corporation.
Yakuza creator Toshirio Nagoshi, Sega game director Yukio Sugino, and Atlus USA president Naoto Hiraoka are on the company’s board.