# Relationship history for MSHA mine 1503579

Current hierarchy: **Goodin Earl → Kentucky Bell Coal Co Inc → 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:** Goodin Earl → No 1 Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Isham Coal Inc → No 1 Strip; 1950-01-01 to 1974-08-01; source msha-controller-operator-history
- **controller_controls_mine:** Walker William H → No 1 Strip; 1950-01-01 to 1974-08-01; source msha-controller-operator-history
- **controller_controls_operator:** Walker William H → Isham Coal Inc; 1950-01-01 to 1974-08-01; source msha-controller-operator-history
- **operator_operates_mine:** Kentucky Bell Coal Co Inc → No 1 Strip; 1974-08-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Goodin Earl → Kentucky Bell Coal Co Inc; 1974-08-02 to current/open; source msha-controller-operator-history