# Relationship history for MSHA mine 1513275

Current hierarchy: **Nead Robert → Har-Don Mining Company Inc → No 1**

- 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:** Coalfield Development Inc → No 1; 1981-12-01 to 1985-09-03; source msha-controller-operator-history
- **controller_controls_mine:** Ratliff James Dale → No 1; 1981-12-01 to 1985-09-03; source msha-controller-operator-history
- **controller_controls_operator:** Ratliff James Dale → Coalfield Development Inc; 1981-12-01 to 1985-09-03; source msha-controller-operator-history
- **operator_operates_mine:** Coalfield Development Inc → No 1; 1985-09-04 to 1986-04-17; source msha-controller-operator-history
- **controller_controls_mine:** Hackney Buford-John R Lark Et Al → No 1; 1985-09-04 to 1986-04-17; source msha-controller-operator-history
- **controller_controls_operator:** Hackney Buford-John R Lark Et Al → Coalfield Development Inc; 1985-09-04 to 1986-04-17; source msha-controller-operator-history
- **operator_operates_mine:** Har-Don Mining Company Inc → No 1; 1986-04-18 to 1987-01-07; source msha-controller-operator-history
- **controller_controls_mine:** Justus Donald Et Al → No 1; 1986-04-18 to 1987-01-07; source msha-controller-operator-history
- **controller_controls_operator:** Justus Donald Et Al → Har-Don Mining Company Inc; 1986-04-18 to 1987-01-07; source msha-controller-operator-history
- **operator_operates_mine:** Har-Don Mining Company Inc → No 1; 1987-01-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Nead Robert → No 1; 1987-01-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nead Robert → Har-Don Mining Company Inc; 1987-01-08 to current/open; source msha-controller-operator-history