# Relationship history for MSHA mine 1508328

Current hierarchy: **Karst Edward W → Karst Robbins Coal Company Inc → No 6 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

- **controller_controls_mine:** Karst Edward W → No 6 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Yellow Star Darby Coal Company Inc → No 6 Mine; 1975-05-05 to 1976-07-28; source msha-controller-operator-history
- **controller_controls_mine:** Karst Edward W → No 6 Mine; 1975-05-05 to 1976-07-28; source msha-controller-operator-history
- **controller_controls_operator:** Karst Edward W → Yellow Star Darby Coal Company Inc; 1975-05-05 to 1976-07-28; source msha-controller-operator-history
- **operator_operates_mine:** Cloverfork Fuel Company → No 6 Mine; 1976-07-29 to 1977-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Lunsford Douglas K → No 6 Mine; 1976-07-29 to 1977-07-31; source msha-controller-operator-history
- **controller_controls_operator:** Lunsford Douglas K → Cloverfork Fuel Company; 1976-07-29 to 1977-07-31; source msha-controller-operator-history
- **operator_operates_mine:** Karst Robbins Coal Company Inc → No 6 Mine; 1977-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Karst Edward W → Karst Robbins Coal Company Inc; 1977-08-01 to current/open; source msha-controller-operator-history