| M & M Specialist- Och Allmäntandvård AB | Se-436 40 Askim | 2024 |
| M a Invest AS | Oslo | 1989 |
| M Angell Holding AS | Moss | 2020 |
| M Erke AS | Oslo | 2025 |
| M Stormo AS | Ankenes | 2025 |
| M Sørensen Holding AS | Narvik | 2014 |
| M&A Molvær Holding AS | Oslo | 2024 |
| M&K-Holding AS | Dal | 2019 |
| M&V Holding AS | Oslo | 2023 |
| M-K Hverdagshelse AS | Gressvik | 2019 |
| M. Gundersen AS | Haugesund | 2019 |
| M. Skaanes AS | Trondheim | 2022 |
| M. Vold Holding AS | Bodø | 2026 |
| M.A. Beauty Clinic AS | Hafslundsøy | 2025 |
| M.Berg AS | Kongsberg | 2023 |
| M.I.N Produksjon SA | Eidsvåg I Romsdal | 2019 |
| M.Johannessen AS | Oslo | 2011 |
| M.Sohrabi Holding AS | Sandvika | 2018 |
| M3ISTER Holding AS | Hamar | 2020 |
| Ma & Mi AS | Oslo | 2008 |
| Maaz Dental AS | Oslo | 2022 |
| Mace Holding Finnsnes AS | Finnsnes | 2021 |
| Mactta Helse AS | Alta | 2012 |
| Madimo Invest AS | Moss | 2012 |
| Madla Naprapatklinikk AS | Hafrsfjord | 2015 |
| Madlaklinikken AS | Hafrsfjord | 2019 |
| Madlakrossen Legesenter Da | Hafrsfjord | 2007 |
| Madoks Consult AS | Oslo | 2017 |
| Mads Stokkelien AS | Kristiansand S | 2023 |
| Madsen & Åsheim AS | Tverlandet | 2020 |
| Madsen Investering AS | Sola | 2025 |
| Madu AS | Bryne | 2013 |
| Mage- Tarmklinikken AS | Arendal | 2014 |
| Magerøy Medical AS | Oslo | 2025 |
| Magespesialisten AS | Bergen | 2018 |
| Magespesialisten Holding AS | Bergen | 2018 |
| Magnat AS | Oslo | 2013 |
| Magnat Corpus Holding AS | Oslo | 2012 |
| Magnat Corpus Invest AS | Oslo | 2012 |
| Magnat Medisinske Senter AS | Oslo | 2021 |
| Magnes Holding AS | Asker | 2003 |
| Magnes Institutt AS | Evenskjer | 2022 |
| MAGNET1 AS | Gjøvik | 2021 |
| Magnoliahelse AS | Jar | 2019 |
| Magnus Evjensvold AS | Oslo | 2025 |
| Mah Services LLC | Nes I Ådal | 2017 |
| Mahavir Neuro AS | Oslo | 2023 |
| Mai Solberg 151083 AS | Gol | 2016 |
| Mairos AS | Sarpsborg | 2008 |
| Maja Hansson Psykiatri Og Kognitiv Terapi AS | Sarpsborg | 2019 |
| Majormed AS | Oslo | 2013 |
| Majorstua Kvinneklinikk AS | Oslo | 2020 |
| Majorstua Tannlegene AS | Oslo | 2016 |
| Majorstuen Helse AS | Oslo | 2023 |
| Majorstuen Legesenter AS | Oslo | 2017 |
| Majorstuen Naprapatsenter Da | Oslo | 2007 |
| Majorstuen Psykologtjeneste AS | Oslo | 2012 |
| Majorstuen Spesialistsenter AS | Oslo | 2020 |
| Majorstuen Tannlegesenter AS | Oslo | 1996 |
| Majorstuhuset Legegruppe Da | Oslo | 2007 |
| Majorstuklinikken AS | Oslo | 2022 |
| Majorstukrysset Legegruppe AS | Oslo | 2018 |
| Makato AS | Grimstad | 2017 |
| Maklami AS | Oslo | 1992 |
| Makuna AS | Oslo | 2007 |
| Malangen Fysioterapi AS | Meistervik | 2012 |
| Maleks AS | Færvik | 2024 |
| Malian AS | Fjerdingby | 2017 |
| Malin Medispa AS | Fornebu | 2024 |
| Malme Fysioterapi AS | Tranby | 2017 |
| Malmedalsklinikken AS | Elnesvågen | 2013 |
| Malterud Østre Da | Reinsvoll | 2018 |
| Malvikbakk Landsby SA | Malvik | 2017 |
| Mamhms AS | Torvastad | 2012 |
| Mandal Spesialistsenter AS | Mandal | 2019 |
| Mandal Tannregulering AS | Mandal | 2024 |
| Manduka AS | Oslo | 2013 |
| Manger Fotklinikk AS | Manger | 2019 |
| Manger Tannlegesenter AS | Manger | 2016 |
| Mangfoldsterapeutene AS | Horten | 2024 |
| Manglerud Fysikalske Institutt Da | Oslo | 1999 |
| Manglerud Tannhelsesenter AS | Oslo | 2005 |
| Manglerud Velvære AS | Oslo | 2015 |
| Mani Dent Tannlege Nazanin Morovatipour AS | Oslo | 2024 |
| Mans Holdings AS | Moss | 2021 |
| Manstad Legekontor AS | Manstad | 2023 |
| Manstad Tannklinikk AS | Manstad | 2021 |
| Manuell Terapi Alta AS | Alta | 2004 |
| Manuell Terapi Klinikken AS | Levanger | 2001 |
| Manuell Terapi Klinikken Østfold AS | Rolvsøy | 2006 |
| Manuellterapeut Am. Meyer-Myklestad AS | Arendal | 2020 |
| Manuellterapeut Ane Nordstrand AS | Leknes | 2026 |
| Manuellterapeut Anne-Marit Haugland AS | Bergen | 2024 |
| Manuellterapeut Bjørn a. Røe AS | Fornebu | 2020 |
| Manuellterapeut Erkki Lintorp AS | Eidsvoll | 2012 |
| Manuellterapeut Fredrik Kristoffersen AS | Sandnes | 2019 |
| Manuellterapeut Geir Moldestad AS | Nordfjordeid | 2015 |
| Manuellterapeut Gyri Yri AS | Slependen | 2015 |
| Manuellterapeut Håvard Sørensen AS | Bodø | 2020 |
| Manuellterapeut Ingrid Elise Heimdal AS | Narvik | 2021 |