| Open Data Foundation | Arizona |
| Open Data Science Conference | Massachusetts |
| Open Dental Software | Oregon |
| Open Domain, Inc. | California |
| Open Education Consortium | Massachusetts |
| Open Education Global | |
| Open Flow, Inc. | Arizona |
| Open Function Computers | |
| Open Geospatial Consortium | |
| Open Government Partnership | District of Columbia |
| Open Grid Forum, Inc. | Indiana |
| Open Home Pro | |
| Open Hub | Massachusetts |
| Open Influence | |
| Open Innovations, LLC | Colorado |
| Open Interactive | |
| Open International | Florida |
| Open Invention Network | North Carolina |
| Open iT, Inc. | |
| Open Ledger, Inc. | |
| Open Lending | |
| Open Menu, LLC | South Carolina |
| Open mHealth | California |
| Open Mobile Alliance SpecWorks | |
| Open Network Operating System | California |
| Open Networking Foundation | California |
| Open Ownership | |
| Open Photonics, Inc. | Florida |
| Open Prairie Ventures | Illinois |
| Open Raven | California |
| Open Road Technologies | Tennessee |
| Open SaaS Directory | |
| Open Sense Solutions, LLC | Wisconsin |
| OPEN Silicon Valley | California |
| Open Sky Software, Inc. | Texas |
| Open Software Technologies, Inc. | Florida |
| Open Solutions for Education, Inc. | Georgia |
| Open Solutions for Education, Inc. | |
| Open Source Experts | Nebraska |
| Open Source Hardware Association | |
| Open Source Initiative | California |
| Open Source Ohio | Ohio |
| Open Source Social Network | |
| Open Source Training | Massachusetts |
| Open Source Training, LLC | Florida |
| Open Space Labs, Inc. | California |
| Open System Imaging | California |
| Open System Technologies | Michigan |
| Open Systems & Networks, Inc. | Florida |
| Open Systems Computing Corporation | New Jersey |