# Relationship history for MSHA mine 4607735

Current hierarchy: **Sutton Charles A → Comfort Run Coal Company Inc → Layland #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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Comfort Run Coal Company Inc → Layland #4; 1989-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Sutton Charles A → Layland #4; 1989-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sutton Charles A → Comfort Run Coal Company Inc; 1989-08-01 to current/open; source msha-controller-operator-history