# Relationship history for MSHA mine 4404084

Current hierarchy: **Austin William C → Met Coal Corp → No 1 Mine**

- 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

- **controller_controls_mine:** Darrell L  Boyd → No 1 Mine; 1974-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Double D Coal Company Inc → No 1 Mine; 1975-05-12 to 1976-08-11; source msha-controller-operator-history
- **controller_controls_operator:** Darrell L  Boyd → Double D Coal Company Inc; 1975-05-12 to 1976-08-11; source msha-controller-operator-history
- **operator_operates_mine:** Thunderbird Coal Company Inc → No 1 Mine; 1976-08-12 to 1976-10-04; source msha-controller-operator-history
- **controller_controls_mine:** Mullins Walter C → No 1 Mine; 1976-08-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mullins Walter C → Thunderbird Coal Company Inc; 1976-08-12 to 1976-10-04; source msha-controller-operator-history
- **operator_operates_mine:** P & M Coal Company Inc → No 1 Mine; 1976-10-05 to 1976-12-10; source msha-controller-operator-history
- **controller_controls_mine:** P & M Coal Company Inc → No 1 Mine; 1976-10-05 to 1976-12-10; source msha-controller-operator-history
- **controller_controls_operator:** P & M Coal Company Inc → P & M Coal Company Inc; 1976-10-05 to 1976-12-10; source msha-controller-operator-history
- **operator_operates_mine:** P & M Coal Company Inc → No 1 Mine; 1976-12-11 to 1977-10-31; source msha-controller-operator-history
- **controller_controls_mine:** Moore Marion → No 1 Mine; 1976-12-11 to 1977-10-31; source msha-controller-operator-history
- **controller_controls_operator:** Moore Marion → P & M Coal Company Inc; 1976-12-11 to 1977-10-31; source msha-controller-operator-history
- **operator_operates_mine:** Met Coal Corp → No 1 Mine; 1977-11-01 to 1979-02-15; source msha-controller-operator-history
- **controller_controls_mine:** Austin William C → No 1 Mine; 1977-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Austin William C → Met Coal Corp; 1977-11-01 to 1979-02-15; source msha-controller-operator-history
- **operator_operates_mine:** Met Coal Corp → No 1 Mine; 1979-02-16 to 1979-06-27; source msha-controller-operator-history
- **controller_controls_mine:** Fleming Doug → No 1 Mine; 1979-02-16 to 1979-06-27; source msha-controller-operator-history
- **controller_controls_operator:** Fleming Doug → Met Coal Corp; 1979-02-16 to 1979-06-27; source msha-controller-operator-history
- **operator_operates_mine:** Met Coal Corp → No 1 Mine; 1979-06-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Austin William C → Met Coal Corp; 1979-06-28 to current/open; source msha-controller-operator-history