- Lo-Rez Vibration Control Ltd
- Loeffler Corporation
- Loggers Schwingungstechnik GmbH
- Loher GmbH
- LOIPART LTD
- LOLO PIPELINE COMPANY Ltd
- LONNE SCANDINAVIA AS
- Look-In-Marine
- Lopolight ApS
- LOTEK A/S
- LOYAL MARINE MANAGEMENT LTD
- LSM Pumper
- LUBMOR Ltd.
- Luoyang Ship Material Engineering Corporation
- LYNGSO MARINE A/S
- M A Corporation
- M Harakhji & Sons
- M.A.S. Ltd.
- M.Juergensen GmbH & Co KG
- M/S. BENZEAR EQUIPMENTS INDIA (P) LTD
- MacArtney A/S
- MacGregor HYDRAMARINE AS
- MacGregor Marine Equipment Ltd
- Machine- & Lierenfabriek C. Kraaijeveld BV
- Machinefabriek L. Straatman BV (Formerly Van de Graaf's werktuig en constructiebouw)
- Machinefabriek Luyt BV
- MACOR Marine GmbH
- MAE IL MARINE SERVICE Co. Ltd.
- MAGISTR SIA
- Magotteaus
- MAHLE INDUSTRIEFILTRATION GMBH
- MAN B&W DIESEL A/S
- MAN Engines & Components UK
- Manabe Zoki Co., Ltd.
- Manfred J.C. Niemann - Marine Division
- Manly Marine Closures Ltd
- Mantsbrite Marine Electr
- Marac Electronics SA
- Marco Marine A/S
- MARE SAFETY AS
- Mareflex GmbH
- MAREL ELECTRONICS S.A.
- MARES SHIPPING GmbH
- MarFlex - Hong Kong
- Marflex B.V.
- Marinall
- MARINE ALUMINIUM AS
- MARINE COMMUNICATIONS Ltd.
- MARINE CONTROL SERVICES AS
- MARINE DEPOT LIMITED
- Marine Digital Co.,Ltd.
- Marine Equipment & Sevices Co.Ltd
- MARINE EXHAUST SOLUTIONS (MES)
- MARINE INDUSTRIAL CONTROL SYSTEMS
- MARINE LINE COATING San.ic ve Dis Tic.A.s.
- Marine Logistics Limited
- Marine Motor Service GmbH
- MARINE NAVIGATION SYSTEMS
- Marine Rescue Technologies Ltd
- Marine Service Jaroszewicz s.c.
- MARINE SPARES BANGLADESH
- Marine Technic
- MARINE TECHNICS
- Marine Technologies LLC
- MARINE WORKS
- MARINELEC
- Marinequip China Co., Ltd.
- Mariner Ship's Equipment
- Mariner Ship's Equipment (Germany) GmbH
- MarineShaft Hirtshals AS
- Marinfloc AB
- MARIOFF CORPORATION OY
- Mariso
- MARIT SA
- MARITEAM A/S
- MARITIME MOBLER AS
- MARITIME MONTERING AS
- Maritime Part
- MARITIME PROGRESS Ltd.
- Maritime Telecommunications
- Marking Services Inc Pte Ltd
- Markus Lifenet Ltd.
- MARLINK AS
- MARSEN Co., Ltd.
- MARTIN BRUUSGAARD & Co. AS
- Maschinenfabrik Wagner GmbH & Co. KG
- Maska Malgorzata Wedzinska
- MASSON MARINE SAS
- Mateo Miletich
- Matsui Iron Works Co Ltd
- Maxwell Marine Europe
- Mayflower Engineering Ltd
- Maynards Europe GmbH
- MAZU MARINE SAFETY APPLIANCES CO.,LTD
- MBT GmbH
- McMurdo Ltd
- MCT BRATTBERG AB
- MecShot Blasting Equipments Pvt Ltd.
- MEDI3 MARINE
- MEDIACOM München GmbH