| Sirius - A CDW Company IL | Wholesale Trade | 0 | — | A |
| Sirius - A CDW Company KS | Wholesale Trade | 0 | — | A |
| Sirius - A CDW Company MD | Wholesale Trade | 0 | — | A |
| Sirius - A CDW Company MN | Wholesale Trade | 0 | — | A |
| Sirius - A CDW Company NE | Wholesale Trade | 0 | — | A |
| Sirius - A CDW Company OH | Wholesale Trade | 0 | — | A |
| Sirius - A CDW Company TX | Wholesale Trade | 0 | — | A |
| Sirius America Insurance Company and Sirius Global Services LLC NY | — | 0 | — | — |
| Sirius Controls Inc. TX | Mining & Extraction | 1 | $90,438 | — |
| SIRIUS GLOBAL SERVICES LLC NY | Finance & Insurance | 5 | $166,567 | — |
| SIRIUS HEALTHCARE, LLC FL | Healthcare & Social Assistance | 2 | $53,893 | — |
| SIRIUS XM RADIO LLC NY | Information & Media | 67 | $143,996 | — |
| Sirmax North America Inc IN | Manufacturing | 0 | — | F |
| Sirna & Sons OH | Wholesale Trade | 0 | — | B |
| Sirna & Sons Produce OH | Wholesale Trade | 0 | — | C |
| Sirois Tool Co., Inc. CT | Manufacturing | 0 | — | D |
| Sirona Dental Inc. NY | Manufacturing | 0 | — | A |
| Sirona Medical, Inc. CA | Professional & Technical Services | 3 | $141,504 | — |
| SIRQ Construction UT | Construction | 0 | — | A |
| Sirrus Software Services Inc FL | Professional & Technical Services | 24 | $72,881 | — |
| SIRSIDYNIX AL | — | 0 | — | — |
| SirSteak Machinery, INc OH | Manufacturing | 0 | — | A |
| SIRTech LLC VA | Professional & Technical Services | 2 | $132,080 | — |
| Sirtex Medical MA | Management of Companies | 0 | — | A |
| Sirtex Medical US Holdings MA | Manufacturing | 0 | — | A |
| SIS Inc - Facebook Site OR | — | 0 | — | — |
| SIS LLC GA | Professional & Technical Services | 2 | $156,050 | — |
| Sisbro, Inc. IL | Transportation & Warehousing | 0 | — | B |
| Sisca Construction Services LLC FL | Construction | 1 | $119,912 | — |
| Sisca Northeast Associates, LLC NY | Construction | 0 | — | A |
| Sisco Marine LLC FL | Manufacturing | 0 | — | F |
| Sisecam Chemicals Wyoming LLC GA | Mining & Extraction | 1 | $151,148 | — |
| Sisel UT | Retail Trade | 0 | — | A |
| Sisense, Inc. NY | Information & Media | 1 | $160,000 | — |
| Siskin Children's Institute TN | — | 0 | — | — |
| Siskin Enterprises, Inc./PermaPlate UT | Finance & Insurance | 0 | — | D |
| Siskin Steel & Supply KY | Wholesale Trade | 0 | — | B |
| Siskin Steel & Supply SC | Wholesale Trade | 0 | — | C |
| Siskin Steel & Supply TN | Wholesale Trade | 0 | — | B |
| Siskiyou Community Health Center OR | Healthcare & Social Assistance | 0 | — | A |
| Siskiyou Corporation OR | Manufacturing | 0 | — | A |
| SISKIYOU FOREST PRODUCTS CA | Manufacturing | 0 | — | F |
| SISKIYOU HOSPITAL CA | Healthcare & Social Assistance | 4 | $126,360 | — |
| SISKIYOU LAKE GOLF RESORT, INC. CA | Accommodation & Food Services | 0 | — | A |
| Siskiyou Technology Consultants CA | Construction | 0 | — | F |
| Siskiyou Telephone CA | Construction | 0 | — | F |
| SISMOS SOLUTIONS, INC. KS | Professional & Technical Services | 11 | $108,203 | — |
| SISSONVILLE FOODLAND INC WV | Retail Trade | 0 | — | C |
| Sissync Marketing Group, LLC SC | Professional & Technical Services | 1 | $86,798 | — |
| Sistah Co-Op MN | — | 0 | — | — |
