| Jungleworks, Inc. | Florida |
| Jungo | |
| Jungo Connectivity Ltd | California |
| Juniata College Computer Science | Pennsylvania |
| Juniata College Mathematics | Pennsylvania |
| Juniper Biomedical | |
| Juniper Biosciences | |
| Juniper Networks, Inc. | California |
| Juniper Payments, LLC | Kansas |
| Juniper Square, Inc. | California |
| Juniper Systems, Inc. | Utah |
| Juniperus | |
| JuniStat Corporation | Delaware |
| Juno by CapitalJ, Inc. | California |
| Juno Capital | Pennsylvania |
| Juno Online Services, Inc. | Washington |
| Juno Technologies | |
| Junot Systems, Inc. | Texas |
| Jupiter | California |
| Jupiter BioMedical Research, Inc. | Florida |
| Jupiter Ed, Inc. | Pennsylvania |
| Jupiter Endovascular, Inc. | |
| Jupiter Intelligence | California |
| Jupiter Neurosciences, Inc. | Florida |
| Jupiter-2, Inc. | Ohio |
| JupiterOne | North Carolina |
| JURA Bio, Inc. | Massachusetts |
| Jurée | Florida |
| Jurimesh | |
| Jurmp, LLC | |
| Jury Systems, Inc. | California |
| Juspay Technologies | |
| Just A Web Company, Inc. | |
| Just Basic | Massachusetts |
| Just Cabling | Texas |
| Just Computers | Wyoming |
| JUST Creative | New York |
| Just Focus, Inc. | California |
| Just IT Solutions, LLC | |
| Just Networks, Inc. | Illinois |
| Just Rite Design | Minnesota |
| Just So Software, Inc. | Arizona |
| JustaNet Computers | Florida |
| JustAskme, Inc. | New York |
| JustCADJobs | California |
| JustCall | California |
| Justdigilab | |
| JUSTEK | Pennsylvania |
| Justice Bid | |
| Justice Systems, Inc. | New Mexico |