In a statement from studio head Atsushi Inaba in an interview with VGC, it seems that the latter is true. When asked about the removal of PlatinumGames from the copyright section, Inaba stated "It's as it looks." followed by "It's as it is written on the website: Astral Chain is their IP and as such there are limitations on how much we feel we should talk about." When asked for further comment, a spokesperson for Platinum said the company was "not in a position to answer."
QUELLE und TEXT: https://gonintendo.com/stories/376125-platinum-games-atsushi-inaba-says-astral-chain-is-nintendo-s-ip

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