# Relationship history for MSHA mine 1502750

Current hierarchy: **United  Company → Wellmore Coal Corp → No 7-A Mine (D)**

- 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:** United  Company → No 7-A Mine (D); 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Harless Creek Fuel Company → No 7-A Mine (D); 1971-02-01 to 1977-08-28; source msha-controller-operator-history
- **controller_controls_mine:** Ratliff Daniel L → No 7-A Mine (D); 1971-02-01 to 1977-08-28; source msha-controller-operator-history
- **controller_controls_operator:** Ratliff Daniel L → Harless Creek Fuel Company; 1971-02-01 to 1977-08-28; source msha-controller-operator-history
- **operator_operates_mine:** Regina Fuel Company → No 7-A Mine (D); 1977-08-29 to 1982-01-21; source msha-controller-operator-history
- **controller_controls_mine:** Ratliff Donald E → No 7-A Mine (D); 1977-08-29 to 1982-01-21; source msha-controller-operator-history
- **controller_controls_operator:** Ratliff Donald E → Regina Fuel Company; 1977-08-29 to 1982-01-21; source msha-controller-operator-history
- **controller_controls_mine:** Stiltner Paul E → No 7-A Mine (D); 1981-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Regina Fuel Company → No 7-A Mine (D); 1982-01-22 to 1982-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Thacker Marvin & Howard Sellards → No 7-A Mine (D); 1982-01-22 to 1982-08-22; source msha-controller-operator-history
- **controller_controls_operator:** Thacker Marvin & Howard Sellards → Regina Fuel Company; 1982-01-22 to 1982-08-22; source msha-controller-operator-history
- **operator_operates_mine:** Carwan Coal Company Inc → No 7-A Mine (D); 1982-08-23 to 1983-04-26; source msha-controller-operator-history
- **controller_controls_operator:** Stiltner Paul E → Carwan Coal Company Inc; 1982-08-23 to 1983-04-26; source msha-controller-operator-history
- **operator_operates_mine:** Wellmore Coal Corp → No 7-A Mine (D); 1983-04-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United  Company → Wellmore Coal Corp; 1983-04-27 to current/open; source msha-controller-operator-history