# Relationship history for MSHA mine 0100980

Current hierarchy: **Drummond Company Inc → Taylor Coal Company Inc → Blount Mountain 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

- **operator_operates_mine:** Taylor Coal Company Inc → Blount Mountain Strip; 1950-01-01 to 1976-04-14; source msha-controller-operator-history
- **controller_controls_mine:** Taylor Walter Scott Sr & Jr → Blount Mountain Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Taylor Walter Scott Sr & Jr → Taylor Coal Company Inc; 1950-01-01 to 1976-04-14; source msha-controller-operator-history
- **operator_operates_mine:** Taylor Coal Company Inc → Blount Mountain Strip; 1976-04-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Drummond Company Inc → Blount Mountain Strip; 1976-04-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Drummond Company Inc → Taylor Coal Company Inc; 1976-04-15 to current/open; source msha-controller-operator-history