| MM | Developer | |
| MM10 | Developer | |
| MM1R3 | Developer | |
| MMAndTheFunkyBunch | Developer | |
| MMEU | Developer | |
| MMGames&more | Developer | |
| MMM | Developer | |
| MMSPeep | Developer | |
| MMXXXVIII | Developer | |
| MMatos | Developer | |
| MNM Software | Developer | |
| MNT Software | Developer | |
| MNWS | Developer | |
| MOGRAFI | Developer | |
| MOKASON | Developer | |
| MOKKA | Developer | |
| MOKSHA GAME | Developer | |
| MONSTER MEOW STUDIOS | Developer | |
| MOONBIT | Developer | |
| MOPS Computer Systems | Developer | |
| MORITZ RULEZ | Developer | |
| MOSHA_NOZIK | Developer | |
| MOSS | DeveloperPublisher | |
| MOSS LTD | Publisher | |
| MOST STUDIOS | Developer | |
| MP Entertainment | DeveloperPublisher | |
| MP2 Games | DeveloperPublisher | |
| MPCA Interactive | DeveloperPublisher | |
| MPS Labs | Developer | |
| MQuero | Developer | |
| MRGZS1 | Developer | |
| MRgove10 | Developer | |
| MRwarlus | Developer | |
| MSG Manuel | Developer | |
| MSL | Publisher | |
| MSSNG | Developer | |
| MSTS 1: Kuju Entertainment | Developer | |
| MSX | Publisher | |
| MSX Club België | DeveloperPublisher | |
| MSX Computer Magazine | DeveloperPublisher | |
| MSX Files | Developer | |
| MSX Magazine | DeveloperPublisher | |
| MSXdev | Publisher | |
| MSio | Developer | |
| MTA Team | DeveloperPublisher | |
| MTDev | Developer | |
| MTK Software | DeveloperPublisher | |
| MTM Games | Publisher | |
| MTO | DeveloperPublisher | |
| MTOJP | Publisher | |