Developer Page: IMJ Entertainment
(dev id no. 10 - prev next)

IMJ (Inter Media Japan) seems to be a company with its finger in a number of tasty media-based pies, including films, advertisement, mobile and such. Everything they've done game-wise seems to be a collaboration with other companies, though, although it seems like they actually own some of them (Mobile & Game Studio is theirs, for one - Bit Town is independent, can't find anything on Flat-Out).
Official Site:

Simple 2000 Series
The Party Unou Quiz (with Mobile & Game Studio), The Uchuu Taisensou (Space War Attack) (with Bit Town)

Simple 2000 Ultimate Series
Taisen! Bakudan Poi Poi (with Flat-Out), Project Minerva Professional (with Flat-Out)

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