| OM CORPORATION | Omaco Enterprises, Inc. ( Phoenix, AZ ) | OMBA S.r.l.( Melzo ) |
| Om Corporation( Okayama ) | Omaha Airport Authority ( Omaha, NE ) | OMBEK LTD. |
| OM Energy Ltd.( London ) | Omaha S.r.l. | OMBU Comercial Distribuidora, S.A.( Barcelona ) |
| OM Group ( Cleveland, OH ) | Omaha Standard, Inc. ( Omaha, NE ) | Ombu Comercial Distribuidora, S.A.( Vilassar De Mar ) |
| OM Group, Inc. ( Cleveland, OH ) | Omala Inc. ( Cheektowaga, NY ) | OMCI S.p.A. Officine Metalmeccaniche Construzioni Industriali ( Modena, IT ) |
| OM Group, Inc. ( Mooney Chemicals, Inc. ) | Oman Perfumery LLC | Omco USA, Inc. ( Milwaukee, WI ) |
| OM Industrial Co., Ltd. ( Oakayama, JP ) | Omark Industries, Inc. | Omcon, Inc. ( Stafford, TX ) |
| Om Industrial Co., Ltd. ( Okayama, JP ) | Omark Industries, Inc. ( Portland, OR ) | OMD Productions AG( Diessenhofen ) |
| OM NOVA Solutions Inc. ( Fairlawn, OH ) | Omasa S.r.l. ( both of, IT ) | Omdoll Paul ( Waukesha, WI ) |
| OM PHARMA | Omat Ltd.( Jerusalem ) | Ome Cosmos Electric Co., Ltd. ( Tokyo, JP ) |
| Om Pharma( Meyrin ) | Omata Manufacturing Co., Ltd.( Yamanashi ) | OME LLC ( Princeton, NJ ) |
| OM PHARMA ( Meyrin 2, CH ) | Omation Corporation ( Mountain View, CA ) | OME TECHNOLOGY CO., LTD. ( TAIPEI COUNTY, TW ) |
| OM SURGICAL (UK) LIMITED ( London, GB ) | Omation Corporation ( Palo Alto, CA ) | OME TECHNOLOGY CO., LTD. ( TAIPEI COUNTY 242, TW ) |
| OM Technology AB | OMAV S.p.A. ( Rodengo Saiano, IT ) | OMEC S.p.A. |
| OM Technology AB ( Stockholm, SE ) | OMAX Corporation | OMEC S.p.A.( Gorla Minore ) |
| OM2P, Inc. ( Manhattan, KS ) | Omax Corporation ( Kent, WA ) | OMEC S.P.A. ( Gorla Minore, IT ) |
| OMA Mfg. Co., Ltd.( Tokyo ) | OMB S.R.L. ( Stenico, IT ) | |
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