| SGSeibu Giken America, Incorporation | Wyomissing | PA | Primary Metal Manufacturing331319 | — | ◇ UNVERIFIED |
| SAShepherd Aluminum Inc | Hanover | PA | Primary Metal Manufacturing331315 | — | ◇ UNVERIFIED |
| SISinnott Industries, INC. | Philadelphia | PA | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| SLSmoyer L M Brass Products, INC. | Bethlehem | PA | Primary Metal Manufacturing331528 | — | ◇ UNVERIFIED |
| SSSovereign Steel Manufacturing, LLC | Allentown | PA | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| SSStation Steel Services, Inc | Milford | PA | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| SBSuperior Bronze CORP | Erie | PA | Primary Metal Manufacturing331522 | — | ◇ UNVERIFIED |
| SMSupreme Manufacutring, INC. | Stoneboro | PA | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| SSSusini Specialty Steels, INC. | Natrona Heights | PA | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| SBSussman Brothers Recycling | Allentown | PA | Primary Metal Manufacturing331492 | — | ◇ UNVERIFIED |
| SSSwedish Steel | Pittsburgh | PA | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| TMTalley Metals, INC. | Hermitage | PA | Primary Metal Manufacturing331111 | — | ◇ UNVERIFIED |
| TWTatano Wire and Steel | Canonsburg | PA | Primary Metal Manufacturing331222 | — | ◇ UNVERIFIED |
| TWTaylor Winefield Corporation | Verona | PA | Primary Metal Manufacturing331111 | — | ◇ UNVERIFIED |
| TTTech Tube Inc/upper Merion | King of Prussia | PA | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| TLTmk-ipsco, LLC. | Ambridge | PA | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| TMT M P Refining Corporation | Malvern | PA | Primary Metal Manufacturing331419 | — | ◇ UNVERIFIED |
| TPTsk Partners, INC. | Erie | PA | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| UEUnion Electric Steel CORP | Burgettstown | PA | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| USUnited States Steel Corporation | Braddock | PA | Primary Metal Manufacturing331111 | — | ◇ UNVERIFIED |
| UWUSA Waste (monroeville Landfill) | Monroeville | PA | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| UOUsdol Osha | Palmerton | PA | Primary Metal Manufacturing331419 | — | ◇ UNVERIFIED |
| USU.s. Steel Corporation | Fairless Hills | PA | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| UTU.s. Tubular Products | Mckeesport | PA | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| VGVernon Gold & Silver Company | Pittsburgh | PA | Primary Metal Manufacturing331492 | — | ◇ UNVERIFIED |
| VSVertical Seal Company | Pleasantville | PA | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| WSWindber Steel, INC. | Windber | PA | Primary Metal Manufacturing331419 | — | ◇ UNVERIFIED |
| ZIZekelman Industries | Farrell | PA | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| ZAZeus Alum Prod/latrobe Plt | Latrobe | PA | Primary Metal Manufacturing331523 | — | ◇ UNVERIFIED |
