# Relationship history for MSHA mine 1507327

Current hierarchy: **Murphy Ronald D → Murphy Elkhorn Coal Company Inc → 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Stewart Auta → No 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Stewart Coal Company → No 1 Mine; 1974-09-18 to 1981-02-16; source msha-controller-operator-history
- **controller_controls_operator:** Stewart Auta → Stewart Coal Company; 1974-09-18 to 1981-02-16; source msha-controller-operator-history
- **controller_controls_mine:** International Minerals & Chemical Corp → No 1 Mine; 1977-07-11 to 1983-04-02; source msha-controller-operator-history
- **operator_operates_mine:** Southern Elkhorn Coal Corp → No 1 Mine; 1981-02-17 to 1981-10-12; source msha-controller-operator-history
- **controller_controls_operator:** International Minerals & Chemical Corp → Southern Elkhorn Coal Corp; 1981-02-17 to 1981-10-12; source msha-controller-operator-history
- **operator_operates_mine:** Big Splash Coal Company Inc → No 1 Mine; 1981-10-13 to 1982-02-07; source msha-controller-operator-history
- **controller_controls_mine:** Mc Glothlin Bernard → No 1 Mine; 1981-10-13 to 1982-02-07; source msha-controller-operator-history
- **controller_controls_operator:** Mc Glothlin Bernard → Big Splash Coal Company Inc; 1981-10-13 to 1982-02-07; source msha-controller-operator-history
- **operator_operates_mine:** Murphy Elkhorn Coal Company Inc → No 1 Mine; 1982-02-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Murphy Ronald D → No 1 Mine; 1982-02-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Murphy Ronald D → Murphy Elkhorn Coal Company Inc; 1982-02-08 to current/open; source msha-controller-operator-history