# Relationship history for MSHA mine 4603976

Current hierarchy: **Hanson PLC → Peabody Coal Company → Mine No 23**

- 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:** Armco Inc → Mine No 23; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Mine No 23; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ellis Creek Coal Company → Mine No 23; 1974-08-01 to 1980-01-09; source msha-controller-operator-history
- **controller_controls_mine:** Protan Sam → Mine No 23; 1974-08-01 to 1980-01-09; source msha-controller-operator-history
- **controller_controls_operator:** Protan Sam → Ellis Creek Coal Company; 1974-08-01 to 1980-01-09; source msha-controller-operator-history
- **operator_operates_mine:** Armco Inc → Mine No 23; 1980-01-10 to 1984-02-26; source msha-controller-operator-history
- **controller_controls_operator:** Armco Inc → Armco Inc; 1980-01-10 to 1984-02-26; source msha-controller-operator-history
- **operator_operates_mine:** Peabody Coal Company → Mine No 23; 1984-02-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Peabody Coal Company; 1984-02-27 to current/open; source msha-controller-operator-history