| A&H Steel LLC | Related taxable corporation/trust | Contributing employer | MO | — |
| A-J Technologies INC | Related taxable corporation/trust | Contributing employer | IL | — |
| ACME Constructorsinc | Related taxable corporation/trust | Contributing employer | MO | — |
| ACME Erectors INC | Related taxable corporation/trust | Contributing employer | MO | — |
| ACME Fence Company | Related taxable corporation/trust | Contributing employer | NC | — |
| Advanced Steel Erectors | Related taxable corporation/trust | Contributing employer | IL | — |
| AERO Bridgeworks | Related taxable corporation/trust | Contributing employer | GA | — |
| Alberici Constructors INC | Related taxable corporation/trust | Contributing employer | MO | — |
| American Bridge Company | Related taxable corporation/trust | Contributing employer | PA | — |
| American IRON & Glass | Related taxable corporation/trust | Contributing employer | OK | — |
| Aquila Industriesllc | Related taxable corporation/trust | Contributing employer | MO | — |
| ARC Union Services LLC | Related taxable corporation/trust | Contributing employer | SC | — |
| ARCH City Ironworks | Related taxable corporation/trust | Contributing employer | MO | — |
| Architectural Wall Systems | Related taxable corporation/trust | Contributing employer | IA | — |
| Automatic Systems INC | Related taxable corporation/trust | Contributing employer | MI | — |
| Axiom Construction Group | Related taxable corporation/trust | Contributing employer | MO | — |
| Barnhart Crane & Rigging | Related taxable corporation/trust | Contributing employer | IA | — |
| Belger Cartage SERV INC | Related taxable corporation/trust | Contributing employer | MO | — |
| BEN HUR Construction CO | Related taxable corporation/trust | Contributing employer | MO | — |
| Berkel and CO | Related taxable corporation/trust | Contributing employer | MO | — |
| BHI Specialty Services LLC | Related taxable corporation/trust | Contributing employer | GA | — |
| Blackford Foundations INC | Related taxable corporation/trust | Contributing employer | IA | — |
| Blue Peaks Industrial | Related taxable corporation/trust | Contributing employer | MO | — |
| Blue Star Erectors LLC | Related taxable corporation/trust | Contributing employer | MO | — |
| BSC Steel INC | Related taxable corporation/trust | Contributing employer | MO | — |