| Sechan Electronics, Inc. | Pennsylvania |
| Seclore | California |
| SECM-GT International, Inc. | |
| Secocha Ventures | Florida |
| Secoda, Inc. | |
| Secom International | California |
| SECOM, Inc. | Colorado |
| Second Avenue Software, Inc. | New York |
| Second Century Ventures, LLC | Illinois |
| Second Dinner Studios, Inc. | |
| Second Front Systems | Delaware |
| Second Generation Ltd | Ohio |
| Second Heart Assist, Inc. | Utah |
| Second Platform, Inc. | California |
| Second Shift Chicago | Illinois |
| Second Source Computers | Delaware |
| Second Source Medical, LLC | California |
| Second Spectrum, Inc. | California |
| Second Star Professional Services | North Carolina |
| Second State | Texas |
| Second Street Creative | |
| SecondSight | Indiana |
| SecondWave Systems, Inc. | |
| SecPod Technologies | California |
| SecqureOne, Inc. | California |
| SecReliant, LLC | New York |
| Secret 6 | California |
| Secret Double Octopus | |
| Secret Sushi | |
| Secretome Therapeutics | |
| Section | California |
| Section 101, LLC | New York |
| Section 9 Cyber Cafe | North Dakota |
| SecTools.Org | California |
| Sector Micro Computer, Inc. | New Jersey |
| Sector Microwave Industries | |
| Sectorlink, LLC | |
| SecturaSOFT | Ohio |
| SecuControl, Inc. | Virginia |
| SecuGen | California |
| SecuPI | New York |
| Secura Bio, Inc. | Nevada |
| SecurAcath | Minnesota |
| SECURalert | Florida |
| Securden, Inc. | Delaware |
| Secure Communication, Inc. | New York |
| Secure Cyber Defense | Ohio |
| Secure Data Recovery Services | California |
| Secure Data Technologies | Illinois |
| Secure Digital Solutions, Inc. | Minnesota |