# Relationship history for MSHA mine 4605277

Current hierarchy: **Woolwine Howard A → Woolwine Coal Company → Cotton Hill No 4**

- 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:** Woolwine Coal Company → Cotton Hill No 4; 1976-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Woolwine Howard A → Cotton Hill No 4; 1976-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Woolwine Howard A → Woolwine Coal Company; 1976-09-01 to current/open; source msha-controller-operator-history