# Relationship history for MSHA mine 2300555

Current hierarchy: **Galveston Houston Company → De Soto Mining Company Inc → Parole Mine And 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: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Milchem Inc → Parole Mine And Plant; 1950-01-01 to 1979-11-14; source msha-controller-operator-history
- **controller_controls_mine:** Baker Hughes Inc → Parole Mine And Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Baker Hughes Inc → Milchem Inc; 1950-01-01 to 1979-11-14; source msha-controller-operator-history
- **controller_controls_mine:** Galveston Houston Company → Parole Mine And Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** De Soto Mining Company Inc → Parole Mine And Plant; 1979-11-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Galveston Houston Company → De Soto Mining Company Inc; 1979-11-15 to current/open; source msha-controller-operator-history