| Research Institute for Mathematical Sciences | Academic & Science |
| Robocom Systems International, Incorporated (de-listed) | Business |
| Research Information Management System | Business |
| Research Instrumentation Management System | Business |
| Response Information Management System | Business |
| Results and Impact Management System | Business |
| Records and Information Management Services | Business |
| Rowan Identity Management System | Business |
| Risk and Insurance Management Society | Business Management |
| Rhode Island Medical Society | Community |
| Removable Interlocking Media Storage | Computing |
| Remote Intelligent Monitoring System | Computing |
| Recirculating Infusion Mashing System | General |
| Recirculating Infusion Mash System | General |
| Recommended Instructional Materials System | General |
| Royal Indian Marine Ship | General |
| Recirculation Infusion Mash System | General |
| Removable Interchangeable Modular System | General |
| Road Information Management System | General |
| Regional Information Management System | General |
| Recruitment in Motorsport | General |
| Riverside, Inyo, Mono, San Bernardino | Governmental |
| Regulatory Information Management Staff | Governmental |
| Roatan Institute for Marine Sciences | Governmental |
| rakhi’s institution of management sciences | Governmental |
| Recirculated Infusion Mash System | Medical |
| Royal Indian Marine Sevice | Military and Defence |
| R&d Information Management System | Military and Defence |
| Registrant Information Management System | Military and Defence |
| Remote Information Management Services | Networking |
| Retarding Ion Mass Spectrometer | Space Science |