# Relationship history for MSHA mine 1517703

Current hierarchy: **Sisk John S & Gerlie V Rickard → Ken-Coal Inc → Deanefield Mine**

- 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:** Ken-Coal Inc → Deanefield Mine; 1995-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Sisk John S & Gerlie V Rickard → Deanefield Mine; 1995-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sisk John S & Gerlie V Rickard → Ken-Coal Inc; 1995-08-01 to current/open; source msha-controller-operator-history