| Plumbers & Pipefitters LCL Unions 502 & 633 PENS Trust Fund | Related tax-exempt org | Provide retirement and disability benefits for eligible participants | KY | 616078145 |
| Plumbers & Pipefitters Local Union Number 502 | Related tax-exempt org | Contributing employer | — | — |
| Plumbers & Pipefitters LCL UN 502 Variable Contrib 401(k) Plan | Related tax-exempt org | Provide retirement benefits for eligible participants | KY | 471870034 |
| Plumbers Local 107 Education & Training Fund | Related tax-exempt org | Contributing employer | — | — |
| Kentucky PIPE Trades Association | Related tax-exempt org | Contributing employer | — | — |
| Plumbers & Pipefitters Local Union Number 633 | Related tax-exempt org | Contributing employer | — | — |
| Plumber & Pipefitter Education & Training Center | Related tax-exempt org | Contributing employer | — | — |
| Kentucky State Building Trades Association | Related tax-exempt org | Contributing employer | — | — |
| ABEL Services | Related taxable corporation/trust | Contributing employer | — | — |
| ACCO INC | Related taxable corporation/trust | Contributing employer | — | — |
| Alliance Comfort Systems | Related taxable corporation/trust | Contributing employer | — | — |
| Alpha Mechanical | Related taxable corporation/trust | Contributing employer | — | — |
| Altstadt PLBG Service INC - Local 633 | Related taxable corporation/trust | Contributing employer | — | — |
| Apcompower | Related taxable corporation/trust | Contributing employer | — | — |
| APEX Mechanical Systems LLC - Local 633 | Related taxable corporation/trust | Contributing employer | — | — |
| August Winter & SONS INC | Related taxable corporation/trust | Contributing employer | — | — |
| AZCO Building | Related taxable corporation/trust | Contributing employer | — | — |
| Barton Malow Company | Related taxable corporation/trust | Contributing employer | — | — |
| BEST Mechanical Services | Related taxable corporation/trust | Contributing employer | — | — |
| Bowen Engineering | Related taxable corporation/trust | Contributing employer | — | — |
| Canam Industrial | Related taxable corporation/trust | Contributing employer | — | — |
| Carrier Building Services | Related taxable corporation/trust | Contributing employer | — | — |
| CFM VR Tesco LLC | Related taxable corporation/trust | Contributing employer | — | — |
| Clark Mechanical LLC | Related taxable corporation/trust | Contributing employer | — | — |
| Climate PROS | Related taxable corporation/trust | Contributing employer | — | — |