# Relationship history for MSHA mine 4603859

Current hierarchy: **Consolidated Sewell Inc → Lady H Coal Company Inc → No 1a Mine**

- 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

- **operator_operates_mine:** Sewell Coal Company → No 1a Mine; 1950-01-01 to 1992-08-16; source msha-controller-operator-history
- **controller_controls_mine:** Pittston Company → No 1a Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Pittston Company → Sewell Coal Company; 1950-01-01 to 1992-08-16; source msha-controller-operator-history
- **controller_controls_mine:** Consolidated Sewell Inc → No 1a Mine; 1992-07-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Lady H Coal Company Inc → No 1a Mine; 1992-08-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Consolidated Sewell Inc → Lady H Coal Company Inc; 1992-08-17 to current/open; source msha-controller-operator-history