# Relationship history for MSHA mine 1510172

Current hierarchy: **Cornett Ellis → Age Coal Inc → No 8 Surface**

- 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:** Frederick & Kelly Inc → No 8 Surface; 1974-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Thornberry James T → No 8 Surface; 1974-10-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cornett Ellis → No 8 Surface; 1975-07-27 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Frederick & Kelly Inc → No 8 Surface; 1976-08-01 to 1977-01-24; source msha-controller-operator-history
- **controller_controls_operator:** Frederick & Kelly Inc → Frederick & Kelly Inc; 1976-08-01 to 1977-01-24; source msha-controller-operator-history
- **operator_operates_mine:** Flattop Mining Inc → No 8 Surface; 1977-01-25 to 1977-03-04; source msha-controller-operator-history
- **controller_controls_operator:** Thornberry James T → Flattop Mining Inc; 1977-01-25 to 1977-03-04; source msha-controller-operator-history
- **operator_operates_mine:** Cirque Coal Company Inc → No 8 Surface; 1977-03-05 to 1977-09-14; source msha-controller-operator-history
- **controller_controls_mine:** Day Walter W → No 8 Surface; 1977-03-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Day Walter W → Cirque Coal Company Inc; 1977-03-05 to 1977-09-14; source msha-controller-operator-history
- **operator_operates_mine:** Age Coal Inc → No 8 Surface; 1977-09-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cornett Ellis → Age Coal Inc; 1977-09-15 to current/open; source msha-controller-operator-history