| SISoelzer, INC Dba Firestone Fabricators | Signal Hill | CA | — | ◇ UNVERIFIED |
| SOSolar of Michigan | Coopersville | MI | — | ◇ UNVERIFIED |
| SISolher Iron, Inc. | San Francisco | CA | — | ◇ UNVERIFIED |
| SFSolid Form Fabrication INC | Mcminnville | OR | — | ◇ UNVERIFIED |
| SRSolid Rock Gate Supply, INC Dba Welding Fabrication Services | Post Falls | ID | — | ◇ UNVERIFIED |
| SFSomerville Fabricators, INC | Mineral Wells | WV | — | ◇ UNVERIFIED |
| SSSonne Steel INC | Smithfield | KY | — | ◇ UNVERIFIED |
| SSSonne Steel INC. | Smithfield | KY | — | ◇ UNVERIFIED |
| SWSonoma Welding & Fabrication LLC | Cape May | NJ | — | ◇ UNVERIFIED |
| SCSonoran Capital Group, INC. | Tucson | AZ | — | ◇ UNVERIFIED |
| SSSopris Steel Construction, Inc. | New Castle | CO | — | ◇ UNVERIFIED |
| SASousa and Demayo INC | North Attleboro | MA | — | ◇ UNVERIFIED |
| SASouth Anna Stair and Rail Company INC | Ashland | VA | — | ◇ UNVERIFIED |
| SASouth Anna Stair & Rail | Norfolk | VA | — | ◇ UNVERIFIED |
| SBSouth Bay Iron, INC | Buena Park | CA | — | ◇ UNVERIFIED |
| SCSouth Central Steel Inc. | Harpersville | AL | — | ◇ UNVERIFIED |
| SCSouth Coast Commercial | San Diego | CA | — | ◇ UNVERIFIED |
| SCSouth County Steel, INC. | West Kingston | RI | — | ◇ UNVERIFIED |
| SCSoutheastern Container | Gautier | MS | — | ◇ UNVERIFIED |
| SMSoutheastern Metal Fabricator | Rockland | MA | — | ◇ UNVERIFIED |
| SUSoutheastern Unipole INC | Bowling Green | KY | — | ◇ UNVERIFIED |
| SFSoutheast Fabricating, INC. | Cape Girardeau | MO | — | ◇ UNVERIFIED |
| SMSoutheast Mechanical Contractors | West Park | FL | — | ◇ UNVERIFIED |
| SASouthern Aluminum Finishing D.b.a. Saf Metal Fab | Atlanta | GA | — | ◇ UNVERIFIED |
| SASouthern Aluminum Finishing D.b.a. Saf Metal Fab | Villa Rica | GA | — | ◇ UNVERIFIED |
| SBSouthern Boiler Service INC. | Lakeland | FL | — | ◇ UNVERIFIED |
| SFSouthern Fabrication Contractors LLC | Chattanooga | TN | — | ◇ UNVERIFIED |
| SFSouthern Fab & Supports, INC. | Conroe | TX | — | ◇ UNVERIFIED |
| SISouthern Industrial Metal Fabricators INC | Smyrna | GA | — | ◇ UNVERIFIED |
| SMSouthern Metal Products CO INC | Louisville | KY | — | ◇ UNVERIFIED |
| SMSouthern Metals Company of Mississippi INC | Laurel | MS | — | ◇ UNVERIFIED |
| SNSouthern Nevada Welding, INC. | Las Vegas | NV | — | ◇ UNVERIFIED |
| SRSouthern Rail and Company, INC. | Fort Walton Beach | FL | — | ◇ UNVERIFIED |
| SRSouthern Rigging and Erection of Louisburg, Incorp | Cary | NC | — | ◇ UNVERIFIED |
| SSSouthern Steel Comapny Limited Liability Company | Charlotte | NC | — | ◇ UNVERIFIED |
| SSSouthern Structural Steel, INC. | Chesapeake | VA | — | ◇ UNVERIFIED |
| SSSouthern Structural Steel Incorporated | Smithfield | VA | — | ◇ UNVERIFIED |
| SSSouthern Structural Steel of Fl, INC | Saint Petersburg | FL | — | ◇ UNVERIFIED |
| SFSouth Florida Aluminum INC. | Lake Worth | FL | — | ◇ UNVERIFIED |
| SFSouthland Fabricators, LLC | Walker | LA | — | ◇ UNVERIFIED |
| SSSouth Shore Iron Works | Chicago | IL | — | ◇ UNVERIFIED |
| SSSouth Sligo Compressor Station | Sligo | LA | — | ◇ UNVERIFIED |
| STSouth Texas Steel Service Company LLC | Victoria | TX | — | ◇ UNVERIFIED |
| SVSouth Valley Mfg | Springfield | MO | — | ◇ UNVERIFIED |
| SHSouthwestern Hollow Metal | Raton | NM | — | ◇ UNVERIFIED |
| SFSouthwest Fabricators | Hugo | OK | — | ◇ UNVERIFIED |
| SSSouthwest Steel Fabrication LLC | Kansas City | MO | — | ◇ UNVERIFIED |
| SSSouthwest Steel, Llc, a Nevada Limited Liability Company | El Mirage | AZ | — | ◇ UNVERIFIED |
| SSpacesonic | San Carlos | CA | — | ◇ UNVERIFIED |
| SWSpanier Welding & Metal Fabrication INC | Paynesville | MN | — | ◇ UNVERIFIED |
