# Relationship history for MSHA mine 3400426

Current hierarchy: **Burlington Resources Inc → Clarkland Inc → Central Mill**

- 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:** Eagle-Picher Industries Inc → Central Mill; 1950-01-01 to 1980-04-21; source msha-controller-operator-history
- **controller_controls_mine:** Eagle-Picher Industries Inc → Central Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eagle-Picher Industries Inc → Eagle-Picher Industries Inc; 1950-01-01 to 1980-04-21; source msha-controller-operator-history
- **operator_operates_mine:** Clarkland Inc → Central Mill; 1980-04-22 to 1981-10-31; source msha-controller-operator-history
- **controller_controls_mine:** St Louis-San Francisco Railway Company → Central Mill; 1980-04-22 to 1981-10-31; source msha-controller-operator-history
- **controller_controls_operator:** St Louis-San Francisco Railway Company → Clarkland Inc; 1980-04-22 to 1981-10-31; source msha-controller-operator-history
- **operator_operates_mine:** Clarkland Inc → Central Mill; 1981-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Burlington Resources Inc → Central Mill; 1981-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Burlington Resources Inc → Clarkland Inc; 1981-11-01 to current/open; source msha-controller-operator-history