# Relationship history for MSHA mine 4001966

Current hierarchy: **Shaker Frank → Tenn-Anderson Mining Company → P-800 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:** M C Anderson Company → P-800 Strip; 1976-03-01 to 1977-03-06; source msha-controller-operator-history
- **controller_controls_mine:** Anderson M C → P-800 Strip; 1976-03-01 to 1977-03-06; source msha-controller-operator-history
- **controller_controls_operator:** Anderson M C → M C Anderson Company; 1976-03-01 to 1977-03-06; source msha-controller-operator-history
- **operator_operates_mine:** Tenn-Anderson Mining Company → P-800 Strip; 1977-03-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Shaker Frank → P-800 Strip; 1977-03-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shaker Frank → Tenn-Anderson Mining Company; 1977-03-07 to current/open; source msha-controller-operator-history