| STSharkey Technology Group INC. Dba C & T Machining | Burbank | CA | — | ◇ UNVERIFIED |
| SESharp Erectors LLC | Wentzville | MO | — | ◇ UNVERIFIED |
| SIShatone, INC. | Whitesburg | GA | — | ◇ UNVERIFIED |
| SCShaw Custom Metal Fabrication LLC | Bluffton | SC | — | ◇ UNVERIFIED |
| SFShaw Fabrication & Manufacturing, INC. | Baton Rouge | LA | — | ◇ UNVERIFIED |
| SFShawnee Fabricators | Shawnee | OK | — | ◇ UNVERIFIED |
| SFShawnee Fabricators, INC. | Shawnee | OK | — | ◇ UNVERIFIED |
| SSShawnee Steel Company | Shawnee | OK | — | ◇ UNVERIFIED |
| SMSheldon Mechanical Corporation | Santa Clarita | CA | — | ◇ UNVERIFIED |
| SSShenkle Steel LLC | Madison | VA | — | ◇ UNVERIFIED |
| SMSherwood Manufacturing Corporation | Northport | MI | — | ◇ UNVERIFIED |
| SBShew Brothers INC. | Marion | IL | — | ◇ UNVERIFIED |
| SMShiner Manufacturing INC. | Shiner | TX | — | ◇ UNVERIFIED |
| SMShoemaker Manufacturing CO | Cle Elum | WA | — | ◇ UNVERIFIED |
| SBShollenbarger - Borella INC Dba Golden State Steel | Fowler | CA | — | ◇ UNVERIFIED |
| SIShoreline Industries, INC. | Portsmouth | VA | — | ◇ UNVERIFIED |
| SIShoremaster INC | Fergus Falls | MN | — | ◇ UNVERIFIED |
| SMShow Me Welding and Fabrication, LLC | Curryville | MO | — | ◇ UNVERIFIED |
| SHS & H Welding INC Dba S & H Metals | Sacramento | CA | — | ◇ UNVERIFIED |
| SMSieckmann Metal Fab INC | Eagle Creek | OR | — | ◇ UNVERIFIED |
| SCSierra CIS, Inc. | Placerville | CA | — | ◇ UNVERIFIED |
| SMSierra Metal Southwest, LLC | Las Vegas | NV | — | ◇ UNVERIFIED |
| SSSigma Steel Incorporated | Bedford | IN | — | ◇ UNVERIFIED |
| SCSignature Craft, LLC | Saint Louis | MO | — | ◇ UNVERIFIED |
| SCSilgan Containers Manufac CORP | Kingsburg | CA | — | ◇ UNVERIFIED |
| SISimko Industrial Fabricators | Hammond | IN | — | ◇ UNVERIFIED |
| SSSimmons Stairways INC. | San Jose | CA | — | ◇ UNVERIFIED |
| SCSimplex Construction Supplies | Blaine | MN | — | ◇ UNVERIFIED |
| SMSimply Mfg (former) | Prairie Du Sac | WI | — | ◇ UNVERIFIED |
| SSSimpson Strong Tie | Riverside | CA | — | ◇ UNVERIFIED |
| SMSincere Metal Works | Amesbury | MA | — | ◇ UNVERIFIED |
| SISindr Industries Inc | Mt Clemens | MI | — | ◇ UNVERIFIED |
| SESinger Equities INC Dba Triad Bellows Design & Mfg | Anaheim | CA | — | ◇ UNVERIFIED |
| SSSingle Source INC | Tallahassee | FL | — | ◇ UNVERIFIED |
| SISitemaster, INC. | Slidell | LA | — | ◇ UNVERIFIED |
| SRSite Resources, LLC | Raleigh | NC | — | ◇ UNVERIFIED |
| SLSjjr, LLC | Taunton | MA | — | ◇ UNVERIFIED |
| SISkaggs Iron Works, INC. | Memphis | TN | — | ◇ UNVERIFIED |
| SKS & K Machineworks Company, INC. | Theodore | AL | — | ◇ UNVERIFIED |
| SCSkrlin Coating & Blasting INC. | Niagara Falls | NY | — | ◇ UNVERIFIED |
| SDSkycomm Development, INC | Helena | MT | — | ◇ UNVERIFIED |
 Skyline Steel Berkeley Facility | Huger | SC | — | ◇ UNVERIFIED |
| Skyline Steel INC. | San Francisco | CA | — | ◇ UNVERIFIED |
| Skyline Steel, INC. | Chandler | AZ | — | ◇ UNVERIFIED |
| SWSleeper Welding | Belmont | NH | — | ◇ UNVERIFIED |
| SLSmart Laser & Manufacturing LLC | Forney | TX | — | ◇ UNVERIFIED |
| SSSmede-son Steel & Building Supply Company | Brighton | MI | — | ◇ UNVERIFIED |
| SISme Industries, INC. | Las Vegas | NV | — | ◇ UNVERIFIED |
| SISme Industries, Incorporated | West Jordan | UT | — | ◇ UNVERIFIED |
| SSSme Steel Contractors, INC. | West Jordan | UT | — | ◇ UNVERIFIED |
