Epic Games has the following press release on their official site.
Epic Games, Inc. announced today an agreement with Square Enix Co. Ltd. granting Square Enix a group-wide license to develop multiple games with Epic’s award-winning Unreal Engine 3 and its breakthrough Unreal Engine 4 technology.
Epic Games Japan, which is providing local support, worked directly with Square Enix on the new license. This sweeping agreement will supplement Square Enix’s proprietary software and ensure the studio is armed with the most powerful game development tools and technologies available across all major platforms.
“Epic has a strong relationship with Square Enix, and it’s an honor to provide their creative and technical talent with the best game technology available for licensing,” said Taka Kawasaki, territory manager of Epic Games Japan. “We look forward to supporting their developers with world-class tools for years to come.”
“Demons’ Score” for iOS and Android, developed by iNiS and published by Square Enix, was created with Unreal Engine 3.