| Sigma Resources LLC PA | Professional & Technical Services | 2 | $90,851 | — |
| SIGMA SOFTWARE LLC TX | Professional & Technical Services | 19 | $110,511 | — |
| Sigma Stretch Films KY | Manufacturing | 0 | — | A |
| Sigma Technologies International, LLC AZ | Professional & Technical Services | 1 | $145,000 | — |
| Sigma Thermal, Inc. GA | Manufacturing | 0 | — | C |
| Sigma Tube OH | Manufacturing | 0 | — | F |
| Sigma Tube Company/DBA Sterling Pipe and Tube, Inc. OH | Manufacturing | 0 | — | F |
| Sigma-Aldrich Corporation MA | Professional & Technical Services | 19 | $134,537 | — |
| Sigma-Aldrich Manufacturing LLC MA | Professional & Technical Services | 1 | $115,000 | — |
| Sigma-Aldrich RTC WY | Manufacturing | 0 | — | A |
| Sigma-Aldrich RTC, Inc. MA | Professional & Technical Services | 1 | $75,000 | — |
| Sigmago Solutions Inc TX | Professional & Technical Services | 5 | $99,328 | — |
| Sigmapharm Laboratories LLC PA | Manufacturing | 0 | — | D |
| SIGMASOFT, LLC. VA | Professional & Technical Services | 2 | $98,000 | — |
| Sigmatech Inc AL | Professional & Technical Services | 0 | — | A |
| SigmaTron International, Inc. CA | Manufacturing | 0 | — | A |
| SigmaTron International, Inc. IL | Manufacturing | 0 | — | A |
| SigmaTron International, Inc. TX | Manufacturing | 0 | — | A |
| Sigmet Corporation PA | Wholesale Trade | 0 | — | A |
| Sign & Awning TX | Construction | 0 | — | F |
| Sign Acquisition LLC NY | Manufacturing | 0 | — | B |
| Sign Art Studio WI | Construction | 0 | — | A |
| Sign Design, Inc. MA | Manufacturing | 0 | — | C |
| Sign Designs MO | Manufacturing | 0 | — | A |
| Sign Effectz, Inc. WI | Other Services | 0 | — | F |
| Sign Erection Ltd TX | Manufacturing | 0 | — | F |
| Sign Fab, Inc MO | Manufacturing | 0 | — | C |
| Sign Faces LLC AL | Manufacturing | 0 | — | F |
| Sign Products Inc MT | Manufacturing | 0 | — | F |
| Sign Source USA OH | Wholesale Trade | 0 | — | A |
| Sign Systems, Inc. NC | Manufacturing | 0 | — | A |
| Sign-Zone, LLC MN | Manufacturing | 0 | — | F |
| SIGNACORP LLC TX | Professional & Technical Services | 2 | $92,581 | — |
| Signal Communications Corp MA | Manufacturing | 0 | — | A |
| Signal Energy, LLC TN | Construction | 2 | $113,797 | A |
| Signal Heating & Air Conditioning Inc. CA | Construction | 0 | — | D |
| Signal Hill Fire Department IL | Public Administration | 0 | — | A |
| SIGNAL INDUSTRIAL PRODUCTS CORP. TN | Wholesale Trade | 0 | — | F |
| Signal International MS | — | 0 | — | — |
| Signal Machine Co GA | Manufacturing | 0 | — | D |
| Signal Media Intelligence Inc. NY | Professional & Technical Services | 1 | $130,000 | — |
| Signal Metal Industries, Inc. TX | Manufacturing | 0 | — | D |
| Signal Peak Silica TX | — | 0 | — | — |
| Signal Peak Silica -Poteet TX | — | 0 | — | — |
| Signal Peak Silica, LLC OK | — | 0 | — | — |
| Signal Restoration MI | Construction | 0 | — | A |
| Signal Restoration Services CA | Construction | 0 | — | A |
| Signal Service Company OH | Construction | 0 | — | F |
| Signal Technologies, Inc. PA | Manufacturing | 0 | — | A |
| Signals Audio Video CA | Construction | 0 | — | A |
