# Relationship history for MSHA mine 1507199

Current hierarchy: **Marwright Coal Company Inc → Marwright Coal Co Inc → No 2 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:** Sproles Ben Et Al → No 2 Mine; 1973-01-15 to 1974-10-14; source msha-controller-operator-history
- **operator_operates_mine:** Ben Sproles Coal Co → No 2 Mine; 1974-01-01 to 1974-10-14; source msha-controller-operator-history
- **controller_controls_operator:** Sproles Ben Et Al → Ben Sproles Coal Co; 1974-01-01 to 1974-10-14; source msha-controller-operator-history
- **operator_operates_mine:** Bill & Ben Coal Company → No 2 Mine; 1974-10-15 to 1975-02-12; source msha-controller-operator-history
- **controller_controls_mine:** Craft Bill → No 2 Mine; 1974-10-15 to 1975-02-12; source msha-controller-operator-history
- **controller_controls_operator:** Craft Bill → Bill & Ben Coal Company; 1974-10-15 to 1975-02-12; source msha-controller-operator-history
- **operator_operates_mine:** Marwright Coal Co Inc → No 2 Mine; 1975-02-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Marwright Coal Company Inc → No 2 Mine; 1975-02-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Marwright Coal Company Inc → Marwright Coal Co Inc; 1975-02-13 to current/open; source msha-controller-operator-history