# Relationship history for MSHA mine 1511839

Current hierarchy: **Goff Terry W → Rope Coal Corp → R B S 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Rope Coal Corp → R B S No 1 Strip; 1979-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Goff Terry W → R B S No 1 Strip; 1979-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Goff Terry W → Rope Coal Corp; 1979-04-01 to current/open; source msha-controller-operator-history