# Relationship history for MSHA mine 1512738

Current hierarchy: **Day Rickey & David C Banks → Roxana Coal Company 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

- **controller_controls_mine:** Howell Corporation → No 1 Mine; 1977-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joseph Brothers Inc → No 1 Mine; 1978-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Lake Coal Company Inc → No 1 Mine; 1981-02-01 to 1982-01-03; source msha-controller-operator-history
- **controller_controls_operator:** Howell Corporation → Lake Coal Company Inc; 1981-02-01 to 1982-01-03; source msha-controller-operator-history
- **operator_operates_mine:** Joseph Brothers Inc → No 1 Mine; 1982-01-04 to 1982-04-28; source msha-controller-operator-history
- **controller_controls_operator:** Joseph Brothers Inc → Joseph Brothers Inc; 1982-01-04 to 1982-04-28; source msha-controller-operator-history
- **operator_operates_mine:** Lake Coal Company Inc → No 1 Mine; 1982-04-29 to 1984-01-08; source msha-controller-operator-history
- **controller_controls_operator:** Howell Corporation → Lake Coal Company Inc; 1982-04-29 to 1984-01-08; source msha-controller-operator-history
- **operator_operates_mine:** Roxana Coal Company Inc → No 1 Mine; 1984-01-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Day Rickey & David C Banks → No 1 Mine; 1984-01-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Day Rickey & David C Banks → Roxana Coal Company Inc; 1984-01-09 to current/open; source msha-controller-operator-history