# Relationship history for MSHA mine 4201219

Current hierarchy: **Gunn R H → R H Gunn Mine Development → Exhaust Shaft Carr Fork 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Centennial Development Company → Exhaust Shaft Carr Fork Mine; 1950-01-01 to 1978-06-06; source msha-controller-operator-history
- **controller_controls_mine:** Bovee David → Exhaust Shaft Carr Fork Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bovee David → Centennial Development Company; 1950-01-01 to 1978-06-06; source msha-controller-operator-history
- **operator_operates_mine:** Thyssen Mining Construction Inc → Exhaust Shaft Carr Fork Mine; 1978-06-07 to 1979-03-10; source msha-controller-operator-history
- **controller_controls_mine:** Thyssen Mining Construction Inc → Exhaust Shaft Carr Fork Mine; 1978-06-07 to 1979-03-10; source msha-controller-operator-history
- **controller_controls_operator:** Thyssen Mining Construction Inc → Thyssen Mining Construction Inc; 1978-06-07 to 1979-03-10; source msha-controller-operator-history
- **controller_controls_mine:** Gunn R H → Exhaust Shaft Carr Fork Mine; 1979-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** R H Gunn Mine Development → Exhaust Shaft Carr Fork Mine; 1979-03-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gunn R H → R H Gunn Mine Development; 1979-03-11 to current/open; source msha-controller-operator-history