| RTC Magazine | California |
| RTD Embedded Technologies, Inc. | Pennsylvania |
| RTE Group, Inc. | Massachusetts |
| RTeams | |
| RTG Data Systems | California |
| RTI International | |
| RTI Products | Michigan |
| Rtist.Studio | Florida |
| RTM Designs | North Carolina |
| RTO Electronics | Michigan |
| RTO Pro | Florida |
| RTP Ventures | New York |
| RTS Consulting-Automation, Inc. | Maryland |
| RTS Data Recovery | California |
| RTS Labs | |
| RTS Solutionz | California |
| RTS, LLC | Virginia |
| RTW Investments, L.P. | |
| RTX Corporation | Virginia |
| RTX Solutions | Minnesota |
| Rubber Ducky Labs | California |
| Rubedo Life Sciences, Inc. | California |
| Rubens Gomes | North Carolina |
| Rubenstein Technology Group, Inc. | New York |
| Rubhu Biologics, Inc. | |
| Rubick AI | |
| Rubicon Biotechnology | California |
| Rubicon Information Systems | Pennsylvania |
| Rubicon Technologies, LLC | New York |
| RubiconMD, Inc. | |
| Rubix Life Sciences | Massachusetts |
| Rubix LS | Massachusetts |
| Rubric Capital Management, L.P. | |
| Rubrik, Inc. | California |
| Ruby Creek Design | |
| Ruby Graphic Design | |
| Ruby Life, Inc. | |
| Ruby on Rails | Illinois |
| Ruby on Rails Tutorial | California |
| Ruby Seven Studios | Nevada |
| Ruby Shore | |
| RubyMotion | Texas |
| RubyXML | California |
| Rucker Kolls, Inc. | California |
| Ruckus Marketing, LLC | |
| Ruckus Networks | |
| RudderStack, Inc. | California |
| Rudzinsky Associates | Massachusetts |
| ruef Creative, LLC | |
| Rugged Depot | Texas |