# Relationship history for MSHA mine 4607888

Current hierarchy: **Bowman Robert A → Elmina Coal Company → Mine No 4a (1)**

- 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:** Bowman Robert A → Mine No 4a (1); 1978-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Elmina Coal Company → Mine No 4a (1); 1990-05-01 to 1990-11-14; source msha-controller-operator-history
- **controller_controls_operator:** Bowman Robert A → Elmina Coal Company; 1990-05-01 to 1990-11-14; source msha-controller-operator-history
- **operator_operates_mine:** Elmina Coal Company → Mine No 4a (1); 1990-11-15 to 1991-08-01; source msha-controller-operator-history
- **controller_controls_mine:** Deel Ernie → Mine No 4a (1); 1990-11-15 to 1991-08-01; source msha-controller-operator-history
- **controller_controls_operator:** Deel Ernie → Elmina Coal Company; 1990-11-15 to 1991-08-01; source msha-controller-operator-history
- **operator_operates_mine:** Elmina Coal Company → Mine No 4a (1); 1991-08-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bowman Robert A → Elmina Coal Company; 1991-08-02 to current/open; source msha-controller-operator-history