| Marion Zimmer Bradley Literary Works Trust | | 2 |
| Maritimes & d'Outre-mer | | 6 |
| Marivole | France | 49 |
| Markosia | Angleterre | 7 |
| Markus Haller | | 8 |
| Marmaille & compagnie | France | 68 |
| Maroli SP Imprints | France | 2 |
| Marpon et Flammarion | France | 3 |
| Marque-Pages | France | 8 |
| MarS | France | 2 |
| Marsam | | 8 |
| Marsilio | Italie | 9 |
| Marsu Productions | France | 88 |
| Martelle | France | 3 |
| Martiens | France | 2 |
| Martin de Halleux | | 8 |
| Martinez Roca | France | 6 |
| Martini & Olive | Etats-Unis | 5 |
| Marval | | 5 |
| Marvel | Etats-Unis | 1234 |
| Mary Clarens | France | 1 |
| Maryshair | | 7 |
| Marysue Rucci Books | Etats-Unis | 5 |
| Mascherato Publishing | | 2 |
| Maskot | France | 1 |
| Maspero | France | 20 |
| Masque d'Or | France | 1 |
| Masque et Cauris | Sénégal | 1 |
| Massilia BD | France | 1 |
| Massin | France | 43 |
| Massolit | Suède | 2 |
| Masson | France | 23 |
| Massons et Cie | France | 1 |
| Massot | | 48 |
| Master Paris-Sorbonne | France | 8 |
| Matador | France | 5 |
| Matériologiques | France | 3 |
| Math Paper Press | | 1 |
| Mathéos | | 3 |
| Matière | | 9 |
| Matin Calme | | 38 |
| Matin Midi Et Soir | France | 1 |
| Matthes & Seitz Berlin | Allemagne | 1 |
| Matyka | | 2 |
| Mauconduit | France | 10 |
| Maurice Bassett | | 1 |
| Maurice Bauche | | 1 |
| Maurice Lamertin | | 1 |
| Maurice Nadeau | France | 32 |
| Mawadab | France | 0 |
| Max Milo | France | 130 |
| Maxi Poche | France | 238 |
| Maxi Tusquets | France | 18 |
| Maxi-Livres | France | 43 |
| Maxima | France | 22 |
| Maxtor | | 3 |
| May et Motteroz | France | 1 |
| Mayfair3 | France | 1 |
| Mazarine | France | 190 |
| Mazeto Square | France | 1 |
| Mazurka | France | 11 |
| MB | France | 3 |
| MC Productions | France | 7 |
| McClelland & Stewart | France | 22 |
| MCD x FSG | Etats-Unis | 14 |
| McElderry | Etats-Unis | 53 |
| McFarland | | 14 |
| McGraw-Hill | | 10 |
| McGray | France | 11 |
| McNally | Etats-Unis | 0 |
| McNidder&Grace | Angleterre | 3 |
| McSweeney's | Etats-Unis | 4 |
| MD | Canada | 4 |
| MdM Production | France | 3 |
| MEB | France | 1 |
| Mécanique générale | Canada | 30 |
| Mecca | Japon | 1 |
| Med'com | France | 1 |
| Medallion Press | Etats-Unis | 3 |
| Meddens | France | 2 |
| Médecine & Hygiène | Suisse | 2 |
| Media 1000 | | 42 |
| Media Blasters | Etats-Unis | 2 |
| Media Rodzina | Pologne | 1 |
| Mediapolitain | | 2 |
| Médiapop | | 20 |
| Médias & Médiations | France | 5 |
| Mediaspaul | France | 28 |
| Medicatrix | Belgique | 1 |
| Médicis | France | 33 |
| Medina Publishing | | 2 |
| Mednyi Vsadnik | Russie | 19 |
| Meduza | France | 1 |
| Meet | | 2 |
| Mégard et Cie | France | 2 |
| Méhari | | 1 |
| Meian | France | 998 |
| Mékiès | | 1 |
| MEL | France | 1 |
| Mélanie Séteun / IRMA | France | 2 |
