Takashi Iizuka
Eggman's name is a reference to the Beatles' song "I Am the Walrus". Though the character was always named Doctor Eggman in Japan, Sega of America changed his name to Doctor Ivo Robotnik when localizing "Sonic the Hedgehog". In a 2016 interview with "Game Informer", Takashi Iizuka revealed Sega of America did this without consulting the development team: