| Company Name | Software Titles |
|---|---|
| Open Source | 712 |
| Oracle | 100 |
| OSISoft | 60 |
| OLYMPUS | 21 |
| Online Media Technologies Ltd. | 18 |
| O2Micro | 17 |
| Omron | 15 |
| Optical Image Technology | 15 |
| OpenText | 14 |
| Open Design Alliance | 8 |
| Oticon A-S | 8 |
| Oberon Media | 7 |
| OEM | 7 |
| OKI Printing Solutions | 7 |
| Option NV | 6 |
| Okidata | 6 |
| OSI Software | 6 |
| Omtool | 6 |
| OnSSI | 5 |
| Ontrack Data Recovery | 5 |
| Open Text Corporation | 5 |
| onOne Software | 5 |
| OPENXTRA Limited | 5 |
| Orbograph | 4 |
| Open Solutions | 4 |
| Omniture | 4 |
| Operation Technology | 4 |
| O&O Software GmbH | 4 |
| On Center Software | 4 |
| OMNIKEY | 4 |
| OpenCube | 4 |
| Openeye | 3 |
| Outerinfo | 3 |
| OCLC | 3 |
| OCS Inventory NG Team | 3 |
| OPNET Technologies | 3 |
| Orneta | 3 |
| OPC Foundation | 3 |
| Orb Networks | 3 |
| OVT | 3 |
| Onset Technology | 2 |
| OmniPage Direct OCR | 2 |
| OJOsoft | 2 |
| Outer Technologies | 2 |
| OEConnection | 2 |
| OCEANIC | 2 |
| Osen Kusnadi | 2 |
| Objectif Lune | 2 |
| Outerlink | 2 |
| Org Professional | 2 |