# Relationship history for MSHA mine 3503762

Current hierarchy: **David J  Davidson; Jerald M  Davidson → J Davidson & Sons Const Inc. → Plant #4**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** David J  Davidson  et al → Plant #4; 1987-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** J Davidson & Sons Const Inc. → Plant #4; 2011-05-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David J  Davidson  et al → J Davidson & Sons Const Inc.; 2011-05-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jerald M  Davidson  et al → J Davidson & Sons Const Inc.; 2011-05-19 to current/open; source msha-controller-operator-history