| Company Logo | Company name | Country | Sector |
|---|---|---|---|
 | OKAMURA Corporation |  Japan | Energy |
 | OKAMURA Corporation | Energy | |
 | Optrontec Inc. |  South Korea | |
 | Oshika Corporation | Japan | Manufacturing, Chemicals |
 | Okitsumo Incorporated | Japan | Manufacturing |
 | Ogura Jewel Industry Co.,Ltd. | Japan | Manufacturing |
 | Oiles Corporation | Japan | Manufacturing |
 | OPHTECS Corporation | Japan | Medical |
 | OHARA INC. | Japan | Manufacturing |
 | OMORI MACHINERY CO., LTD. | Japan | Manufacturing |
 | Ohmi Press Works & Forging Co., Ltd. | Japan | Manufacturing |
 | Okabe | Japan | Manufacturing |
