# Relationship history for MSHA mine 3605523

Current hierarchy: **Shaffer Cecil J → Shaffer Coal Company → Shaffer Strip No 3**

- 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:** Shaffer Coal Company → Shaffer Strip No 3; 1975-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Shaffer Cecil J → Shaffer Strip No 3; 1975-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shaffer Cecil J → Shaffer Coal Company; 1975-04-01 to current/open; source msha-controller-operator-history