# Relationship history for MSHA mine 1507105

Current hierarchy: **Dotson Roland → B & D Coal Inc → 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

- **operator_operates_mine:** Sanson Coal Company Inc → No 1 Mine; 1974-01-01 to 1976-05-05; source msha-controller-operator-history
- **controller_controls_mine:** Sanson Coal Company Inc → No 1 Mine; 1974-01-01 to 1976-05-05; source msha-controller-operator-history
- **controller_controls_operator:** Sanson Coal Company Inc → Sanson Coal Company Inc; 1974-01-01 to 1976-05-05; source msha-controller-operator-history
- **operator_operates_mine:** B & D Coal Inc → No 1 Mine; 1976-05-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dotson Roland → No 1 Mine; 1976-05-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dotson Roland → B & D Coal Inc; 1976-05-06 to current/open; source msha-controller-operator-history