- Current Corporation
- Cygnus Instruments Ltd
- D I DAVIT INTERNATIONAL GmbH
- D. Koronakis SA
- Dae Kwang Co Ltd
- DAEDONG MARINE TECH
- DAEHAN GENERATOR CO.,LTD
- Daehwa Engineering Service Co., Ltd.
- Daeyang Electric Co., Ltd.
- Daihatsu Diesel Mfg Co Ltd
- Dalian Dahui Science & Technology Development Co., Ltd.
- Dalian Marine Valve Co., Ltd.
- Damen Anchor & Chain Factory (AKF)
- Dan Marine (Canada) Limited
- DANFOSS A/S
- Daniamant Electronics A/S (formerly Uni-Safe Electronics A/S)
- Danish Crane Building AS
- DANISH MARINE SYSTEM A/S
- DANSK RADIO AS
- DAPE Consultants, Engineering & Representatives Ltd.
- Dasic Marine Ltd
- DATA HIDROLIK MAKINA SANAYI AS
- Datema Delfzijl BV
- Davey & Company London Ltd
- De Gerlien-Van Tiem BV
- DECKMA GmbH
- Deckma Hamburg GmbH
- DEGUSAN DENIZCILIK SAN. TIC. Ltd. Sti.
- Deif (UK) Ltd
- DEIF A/S
- DELMAR DENIZCILIK TASIMACILIK TURIZM SANAYI VE TICARET Lyd. Sti.
- Delta Fire Ltd
- DELTA GEMI DONATIM LTD. STI
- Delta Rigging and Tools
- DelVal Flow Controls Private Limited
- DEMP A/S
- DENIZSAN GROUP OF COMPANIES
- Dennis Nakakita SA
- DENO COMPRESSORS
- DENPAR MAKINA A.S.
- DESARROLLO TECNICAS INDUSTRIALES DE GALICIA S.A.
- DESMI B.V.
- DESMI Pumping Technology A/S
- DESMI Ro-Clean A/S
- DEUTZ AG
- Dezhou Hengli Electrical Machinery Co., Ltd.
- DHRUV Pipeline Products Pvt Ltd
- Diamond Sea Glaze
- Dibblee Tools Ltd
- DICKER STEELFAST PTE LTD
- DICKINSON MARINE
- DIESEL GEN SERVICES
- Diesel Systems Plant
- DIGITAL SYMBOL CO.,LTD
- DIKO ELEKTRIKLI CIHAZLAR SAN. VE TIC. AS
- DINO PAOLI SRL
- DITECH SCANDINAVIA AS
- DIXON MANUFACTURING Ltd.
- DK Industrial Co., Ltd.
- DLK Ventilatoren GmbH
- DM Alscott marine & Offshore HVAC Ltd.
- DMU MARINE CO., LIMITED
- Dolphin Maritime Software Ltd
- Dometic Marine
- DONG-I Industrial Co
- Donggang Weiyuan Fuel Injection Equipment Co.,Ltd
- DongHwa Entec
- DONGHYUN MARINE EQUIPMENT CO.,LTD
- Dongnam Marine Crane
- Dongtai Haipeng Marine Fittings Factory
- Dongying Xinyu Precision Metal Co.,Ltd
- DOORMET Ltd.
- DOOSAN ENGINE Co., Ltd.
- DOUBLE D MARINE EQUIPMENT BV
- DPI CO., LTD
- Dr. E. Horn GmbH
- Dr. Shrink, Inc.
- Drahtseilwerk GmbH
- Dredge Yard UAE
- DRUMET Ropes and Wires Ltd.
- DSB ENGINEERING CO.,LTD.
- DSB Offshore Ltd
- DSE BEARING Co., Ltd.
- Dulang Engineering Sdn Bhd
- Duncan Propellers Ltd
- Duramax Marine LLC
- Durapipe UK(Head office)
- DURASTIC Ltd.
- Dutch Thrustleader Marine Propulsion B.V.
- Dutchi Motors B.V.
- Dutton-Lainson Company
- DVC International ApS
- DYM CO LTD
- DYNALCO
- Dynamar B.V.
- Dynamic Marine Systems B.V.
- Eaci Orfeo International
- EagleBurgmann KE A/S
- Eastern Foundry Limited
- EASTONE INTERNATIONAL(HK) CO.,LTIMITED