| Title | Games |
 | Mad Doc Software LLC Lawrence, MA | 1 |
 | MadCat Interactive Location Unknown | 0 |
 | Magenta Software Ltd. Albert Dock, Liverpool, UK | 0 |
 | Mass Media Moorpark, CA | 1 |
 | Massive Entertianment Sweden | 0 |
 | Mattel Interactive El Segundo, California | 0 |
 | Maxis Studios Emeryville, California | 1 |
 | Media Vision Japan | 0 |
 | MercurySteam Spain | 4 |
 | Metro 3D Location Unknown | 0 |
 | Metropolis Software Poland | 2 |
 | Microids Global | 0 |
 | Microsoft Redmond, Washington | 64 |
 | Microsoft Game Studios Japan Japan | 4 |
 | Midway Entertainment Location Unknown | 6 |
 | Midway Studios Austin Austin, TX | 1 |
 | MIG Entertainment Location Unknown | 0 |
 | Milestone Location Unknown | 18 |
 | Mindware Czech Republic | 2 |
 | Mithis Location Unknown | 0 |
 | MixMax Location Unknown | 0 |
 | Monolith Productions Location Unknown | 9 |
 | Monster Games Location Unknown | 0 |
 | Monster Games Hamburg, Germany | 0 |
 | Mucky Foot Productions Surrey, UK | 0 |
 | Mistwalker Location Unknown | 2 |
 | MumboJumbo LLC Location Unknown | 1 |
 | Majesco Location Unknown | 1 |
 | MTV Games Location Unknown | 0 |
 | Mine Loader Software Location Unknown | 1 |
 | Mondo Media Location Unknown | 3 |
 | Marvelous Interactive Location Unknown | 1 |
 | MAXUM Games Location Unknown | 1 |
 | Midway Studios Chicago Location Unknown | 1 |
 | Masterpiece Location Unknown | 1 |
 | Merscom LLC Location Unknown | 1 |
 | Monsune Moon Location Unknown | 2 |
 | Metacreature Games Location Unknown | 0 |
 | Mo Location Unknown | 1 |
 | Mommy's Best Games Location Unknown | 5 |
 | Mere Mortals Location Unknown | 1 |
 | Metropolis Soft. Location Unknown | 1 |
 | Moss Ltd. Location Unknown | 3 |
 | Monumental Games Location Unknown | 2 |
 | Mexond Location Unknown | 2 |
 | Madcat327 Location Unknown | 1 |
 | Mana Bomb Game Studios Location Unknown | 1 |
 | m00nkeh Location Unknown | 1 |
 | Mindscape Location Unknown | 1 |
 | Microsoft Research Location Unknown | 1 |
 | Most Wanted Location Unknown | 1 |
 | Monkeypaw Games Location Unknown | 1 |
 | Mojang AB Location Unknown | 0 |
 | Mastiff Location Unknown | 2 |
 | Mad Catz Location Unknown | 1 |
 | Miniclip Location Unknown | 10 |
 | M2 Location Unknown | 5 |
 | Mando Productions Location Unknown | 1 |
 | Mossmouth Location Unknown | 1 |
 | Moon Spider Studio Location Unknown | 1 |
 | Maximum Games Location Unknown | 1 |
 | Might and Delight Location Unknown | 1 |
 | MaxNick Location Unknown | 1 |
 | Merge Interactive Location Unknown | 3 |
 | Mokus Location Unknown | 1 |
 | Marker Metro Location Unknown | 2 |
 | Monkey Bar Games Location Unknown | 1 |
 | MachineGames Location Unknown | 1 |
 | Mighty Rocket Studio Location Unknown | 1 |
 | Magic Pockets Location Unknown | 1 |
 | Mediatonic Location Unknown | 1 |
 | MLB Location Unknown | 1 |
 | Microsoft Studios Location Unknown | 1 |
 | Mouldy Toof Location Unknown | 1 |
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