# Relationship history for MSHA mine 3303660

Current hierarchy: **Kemmerling Lowry R → Ryland & Ryland Inc → Rehoboth**

- 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:** Ryland & Ryland Inc → Rehoboth; 1977-11-01 to 1979-08-02; source msha-controller-operator-history
- **controller_controls_mine:** Kemmerling Lowry R → Rehoboth; 1977-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kemmerling Lowry R → Ryland & Ryland Inc; 1977-11-01 to 1979-08-02; source msha-controller-operator-history
- **operator_operates_mine:** New Lexington Coal Company Of Ohio Inc → Rehoboth; 1979-08-03 to 1979-12-17; source msha-controller-operator-history
- **controller_controls_mine:** New Lexington Coal Company Of Ohio Inc → Rehoboth; 1979-08-03 to 1979-12-17; source msha-controller-operator-history
- **controller_controls_operator:** New Lexington Coal Company Of Ohio Inc → New Lexington Coal Company Of Ohio Inc; 1979-08-03 to 1979-12-17; source msha-controller-operator-history
- **operator_operates_mine:** Ryland & Ryland Inc → Rehoboth; 1979-12-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kemmerling Lowry R → Ryland & Ryland Inc; 1979-12-18 to current/open; source msha-controller-operator-history