# Relationship history for MSHA mine 0101400

Current hierarchy: **Webb Martin B → Rock City Coal & Equipment Inc → Rock City Pit No 5**

- 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:** Sun-Up Coal Company Inc → Rock City Pit No 5; 1975-08-15 to 1983-10-16; source msha-controller-operator-history
- **controller_controls_mine:** Sun-Up Coal Company Inc → Rock City Pit No 5; 1975-08-15 to 1983-10-16; source msha-controller-operator-history
- **controller_controls_operator:** Sun-Up Coal Company Inc → Sun-Up Coal Company Inc; 1975-08-15 to 1983-10-16; source msha-controller-operator-history
- **operator_operates_mine:** Rock City Coal & Equipment Inc → Rock City Pit No 5; 1983-10-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Webb Martin B → Rock City Pit No 5; 1983-10-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Webb Martin B → Rock City Coal & Equipment Inc; 1983-10-17 to current/open; source msha-controller-operator-history