# Relationship history for MSHA mine 1504101

Current hierarchy: **Bartley & Ratliff Coal Co → Bartley & Ratliff Coal Co → Mine No 122 A**

- 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:** Bartley & Ratliff Coal Co → Mine No 122 A; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bartley & Ratliff Coal Co → Mine No 122 A; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bartley & Ratliff Coal Co → Bartley & Ratliff Coal Co; 1950-01-01 to current/open; source msha-controller-operator-history