# Relationship history for MSHA mine 4400624

Current hierarchy: **Justus Roy → J & L Coal Company → Mine No 1**

- 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

- **operator_operates_mine:** Dotson Coal Company Inc → Mine No 1; 1950-01-01 to 1970-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Dotson Lonnie → Mine No 1; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dotson Lonnie → Dotson Coal Company Inc; 1950-01-01 to 1970-12-31; source msha-controller-operator-history
- **operator_operates_mine:** J & L Coal Company → Mine No 1; 1971-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Justus Roy → Mine No 1; 1971-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Justus Roy → J & L Coal Company; 1971-01-01 to current/open; source msha-controller-operator-history