# Relationship history for MSHA mine 1514615

Current hierarchy: **Carl R  Johnson → Dema Coal Company Inc → Dema #2**

- 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:** Patton Branch Coal Company Inc → Dema #2; 1984-05-01 to 1987-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Hall Kenneth → Dema #2; 1984-05-01 to 1987-07-19; source msha-controller-operator-history
- **controller_controls_operator:** Hall Kenneth → Patton Branch Coal Company Inc; 1984-05-01 to 1987-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Carl R  Johnson et al → Dema #2; 1985-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Dema Coal Company Inc → Dema #2; 1987-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Carl R  Johnson et al → Dema Coal Company Inc; 1987-07-20 to current/open; source msha-controller-operator-history