# Relationship history for MSHA mine 1509705

Current hierarchy: **Brock Ramsey → Ramco Coal Company Inc → Flat Rock No 1 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:** Swartwood T Marshall → Flat Rock No 1 Mine; 1975-06-02 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Coal Fuels Inc → Flat Rock No 1 Mine; 1976-05-17 to 1976-08-17; source msha-controller-operator-history
- **controller_controls_operator:** Swartwood T Marshall → Coal Fuels Inc; 1976-05-17 to 1976-08-17; source msha-controller-operator-history
- **operator_operates_mine:** Ramco Coal Company Inc → Flat Rock No 1 Mine; 1976-08-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Brock Ramsey → Flat Rock No 1 Mine; 1976-08-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brock Ramsey → Ramco Coal Company Inc; 1976-08-18 to current/open; source msha-controller-operator-history