| Company | Location |
|---|---|
| Optical Additives GmbH | Staufen, Switzerland |
| Optium Corp. | Chalfont, Pennsylvania, United States |
| Optiva Inc. | South San Francisco, California, United States |
| Opto Solutions Group | Atlanta, Georgia, United States |
| Opto-Mechanical Engineering Inc. | Toronto, Ontario, Canada |
| Optobionics Corp. | Naperville, Illinois, United States |
| Optolab Microsystems GmbH | Erfurt, Germany |
| Optomec Inc. | Albuquerque, New Mexico, United States |
| Orbital Traction | Houston, Texas, United States |
| Orchid BioSciences Inc. | Princeton, New Jersey, United States |
