| Portable Power Systems | Missouri |
| Portable Technology Solutions | New York |
| Portage CyberTech, Inc. | |
| PortageCommunications | Idaho |
| Portal Biotechnologies | Massachusetts |
| Portal Innovations, LLC | Illinois |
| Portal Instruments | Massachusetts |
| Portal Planet | Ohio |
| Portal Systems, Inc. | Virginia |
| Portal Web Hosting | South Dakota |
| PortalOne, Inc. | California |
| Portative Technologies | Indiana |
| Portent, Inc. | Washington |
| Porterville College | California |
| Portfol | Pennsylvania |
| Portfolia | California |
| Portfolio Aid, Inc. | |
| Portfolio Science, Inc. | Connecticut |
| Portico Capital Securities, LLC | Connecticut |
| Porticos, Inc. | |
| Portkey SEO Solutions | |
| Portland Laptop Repair, LLC | Oregon |
| Portland Macintosh Users Group | Oregon |
| Portland Managed Services | Oregon |
| Portland Perl Mongers | Oregon |
| Portland Seed Fund | Oregon |
| Portland Software Developers | |
| Portland State University Department of Computer Science | Oregon |
| Portland State University Department of Electrical and Computer Engineering | Oregon |
| Portland State University Fariborz Maseeh Department of Mathematics and Statistics | Oregon |
| Portland Support Computer Repair | Oregon |
| Portland Website Company | |
| Portland Webworks | Maine |
| Portlandia Cloud Services | Oregon |
| Portley, Inc. | |
| Portline, Inc. | Oregon |
| Portnov Computer School | California |
| Portnox | Texas |
| Portola Systems, Inc. | California |
| Porton Advanced | |
| Porton Advanced Solution Ltd | New Jersey |
| Portrait Displays, Inc. | California |
| Portrett Pharmaceuticals | |
| Portside Marketing, LLC | |
| Portside, Inc. | North Carolina |
| Portsmith Technologies | Idaho |
| Portusx, LLC | |
| Portworx | California |
| PortX | Washington |
| POS International, Inc. | Florida |