# Relationship history for MSHA mine 1800568

Current hierarchy: **Thrasher Lorraine H → Georges Creek Company → No 1 Strip**

- 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:** Carl Del Signore Family Trust → No 1 Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Georges Creek Company → No 1 Strip; 1975-03-01 to 1978-11-30; source msha-controller-operator-history
- **controller_controls_mine:** Thrasher Lorraine H → No 1 Strip; 1975-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thrasher Lorraine H → Georges Creek Company; 1975-03-01 to 1978-11-30; source msha-controller-operator-history
- **operator_operates_mine:** Buffalo Coal Company Inc → No 1 Strip; 1978-12-01 to 1980-05-01; source msha-controller-operator-history
- **controller_controls_operator:** Carl Del Signore Family Trust → Buffalo Coal Company Inc; 1978-12-01 to 1980-05-01; source msha-controller-operator-history
- **operator_operates_mine:** Georges Creek Company → No 1 Strip; 1980-05-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thrasher Lorraine H → Georges Creek Company; 1980-05-02 to current/open; source msha-controller-operator-history