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| Mac Safety Services Limited | Lancashire Fy7 6Qh | 2021 |
| Maca Business Limited Nuf | Ulset | 2010 |
| Macama Organisasjonsutvikling AS | Drammen | 2009 |
| Macasto AS | Trondheim | 2025 |
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| Maccan AS | Molde | 2019 |
| Maccon AS | Horten | 2020 |
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| Mace Utvikling AS | Angvik | 2019 |
| Maceda AS | Borøy | 1959 |
| Macerealm Limited | Cleveland Ts16 9Bh | 2013 |
| Macgregor Sweden AB | Se-429 30 Västra Frölunda | 2013 |
| Mach AS | Ottestad | 2016 |
| Mach Consulting Da | Gurskøy | 2010 |
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| Machs Engineering Ltd | London Wc1N 3Ax England | 2023 |
| Maciej Kowalski | Pl-28 425 Chroberz | 2018 |
| Mack Ad AS | Tromsø | 2021 |
| Mack Anlegg & Oppmåling AS | Stord | 2013 |
| Mack Bygg Prosess AS | Nesøya | 2005 |
| Mack Concepts AS | Tromsø | 2020 |
| Mack DC AS | Tromsø | 2021 |
| Mack En AS | Tromsø | 2020 |
| Mack to AS | Tromsø | 2020 |
| Mackinlay Well Engineering Limited | G3 6Ef Glasgow | 2013 |
| Macleod Subsea Ltd | Dunfermline Fife Ky11 8Tl Scotland | 2014 |
| Macman AS | Halden | 2015 |
| Macpherson Invest AS | Straumsgrend | 2012 |
| Macpoint Ans | Tønsberg | 1991 |
| Macquarie Bank Europe Designated Activity Company Nuf | Oslo | 2026 |
| Macquarie Bank Limited Nuf | Au-2000 Sydney Nsw | 2026 |
| Mad Arkitekter AS | Oslo | 2015 |
| Mad AS | Oslo | 1997 |
| Mad Global AS | Oslo | 2015 |
| Mad Island Media AS | Oslo | 2017 |
| Mad Media AS | Oslo | 2020 |
| Madac AS | Spongdal | 2005 |
| Madaco AS | Slependen | 2022 |
| Madan Energy Consultants AS | Stavanger | 2022 |
| Made Bay Voraa AS | Oslo | 2024 |
| Made by Hvesser AS | Moss | 2025 |
| Made by TRK AS | Bergen | 2018 |
| Made by Wood AS | Oslo | 2018 |
| Made Entertainment Group AS | Bergen | 2019 |
| Made in Motion AS | Bjørnemyr | 2025 |
| Made Management AS | Bergen | 2018 |
| Made With Hart Oslo AS | Oslo | 2016 |
| Madel Products AS | Kråkerøy | 2015 |
| Madian Holding AS | Askim | 2001 |
| Madisa AS | Oslo | 2008 |
| Madisa Consulting AS | Trøgstad | 2014 |
| Madison Consulting AS | Moss | 2022 |
| Madison Sun AS | Oslo | 2008 |
| Madnes Da | Nes På Hedmarken | 2014 |
| Madost AS | Fetsund | 2014 |
| Madriane AS | Bønes | 2007 |
| Madrigal AS | Moelv | 2013 |
| Madrugada Music AS | Melbu | 2019 |
| Mads Consulting AS | Drammen | 2014 |
| Mads Helle Eiendom AS | Førde | 2005 |
| Mads Mekker AS | Lommedalen | 2025 |
| Mads Nordsveen AS | Oslo | 2020 |
| Madsen AS | Godvik | 2010 |
| Mae AS | Bosberg | 2017 |
| Mae Holding AS | Oslo | 2022 |
| Mae Prosjekt AS | Tranby | 2024 |
| Maecap AS | Staubø | 2014 |
| Maelma Holding AS | Sponvika | 2022 |
| Maelstrom AS | Oslo | 2013 |
| Maeo AS | Bergen | 2025 |
| Maepo AS | Fagerstrand | 2021 |
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| Maersk Olje Og Gas | Stavanger | 2010 |
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| Maestranza AS | Ålesund | 2018 |
| Maestro Consulting AS | Oslo | 2015 |
| Maestro Profil AS | Bryne | 2021 |
| Maffei Investment Holding AS | Bergen | 2020 |
| Maffeis Engineering Norge AS | Alta | 2019 |
| Mafor Management AS | Oslo | 2026 |
| Mag-Nor Holding AS | Ski | 2020 |
| Mag-S Regnskap AS | Eiksmarka | 2007 |
| Magasin Yng Sartor AS | Follese | 2015 |
| Magent AS | Oslo | 2019 |
| Magenta Interiørarkitekter AS | Jar | 1999 |
| Magic AS | Lørenskog | 2024 |
| Magic Booking & Management AS | Ørsta | 2017 |
| Magic Capital AS | Oslo | 2024 |
| Magic Machining Services Limited Nuf | Klepp Stasjon | 2024 |
| Magino Luksus Frakt Da | Stabekk | 2000 |
| Magino Snacks Da | Stabekk | 2000 |
| Magisk Potet AS | Charlottenlund | 2003 |
| Magiskeminner AS | Tromsø | 2024 |
| Magisterium Urbanum AS | Tangen | 2022 |
| Magix AS | Oslo | 2022 |
| Magixi AS | Os | 2018 |