| Orijin Media | Wyoming |
| ORIL, Inc. | |
| Orinoco 360, LLC | |
| Orion | |
| Orion Advisor Solutions | Nebraska |
| Orion Communications, Inc. | Texas |
| Orion Concepts, LLC | New York |
| Orion Corporation | |
| Orion Fans | Texas |
| Orion Genomics | Missouri |
| Orion Health | California |
| Orion Healthcare Technology, Inc. | Nebraska |
| Orion HiTek, Inc. | Florida |
| Orion Integrated Biosciences, Inc. | Kansas |
| Orion Labs, Inc. | California |
| Orion Management, LLC | Virginia |
| Orion Mobility | Connecticut |
| Orion Monitoring Systems, Inc. | Utah |
| Orion Network Solutions | Virginia |
| Orion Resources Partners | |
| Orion Security | |
| Orion Space Solutions | |
| ORION Systems, Inc. | Pennsylvania |
| Orion Talent | North Carolina |
| Orion Telecom | Arizona |
| Orion Telecom Networks, Inc. | Arizona |
| Orion Therapeutics | |
| Orionis Biosciences | Massachusetts |
| OrisDX, Inc. | |
| Orizuru Therapeutics, Inc. | |
| Orka Automation | Michigan |
| Orkes | |
| Orkiv Retail Solutions | |
| Orlando Clinical Research Center | |
| Orlando Economic Partnership | |
| Orlando Network Cabling & Fiber Optic | Florida |
| Orlando SEO | Florida |
| OrlandoSEOWorld.com | |
| OrLANtech | Florida |
| Orleans Technical College | Pennsylvania |
| Orlucent, Inc. | California |
| Ormandy | Georgia |
| Ormat Technologies, Inc. | |
| ORMEC Systems Corporation | New York |
| Ormsby's Computer Systems | Vermont |
| Orna Therapeutics, Inc. | |
| ORO Labs | California |
| Oro, Inc. | California |
| Orochem Technologies, Inc. | |
| Orogen Therapeutics | |