# Relationship history for MSHA mine 4103374

Current hierarchy: **John  Hughes → J W Hughes Excavation, Inc. → Tilden Plant**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Zeotech Corporation → Tilden Plant; 1986-02-01 to 2021-06-28; source msha-controller-operator-history
- **controller_controls_mine:** O Paul  Leonard Jr → Tilden Plant; 1986-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** O Paul  Leonard Jr → Zeotech Corporation; 1986-02-01 to 2021-06-28; source msha-controller-operator-history
- **operator_operates_mine:** J W Hughes Excavation, Inc. → Tilden Plant; 2021-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John  Hughes → Tilden Plant; 2021-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Hughes → J W Hughes Excavation, Inc.; 2021-06-29 to current/open; source msha-controller-operator-history