# Relationship history for MSHA mine 4405579

Current hierarchy: **Blankenship Ralph → Comanche Coal Corp → Mine No 3**

- 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:** Smith David → Mine No 3; 1980-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Blankenship Ralph → Mine No 3; 1980-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Snowball Coal Corp → Mine No 3; 1981-01-01 to 1982-03-22; source msha-controller-operator-history
- **controller_controls_operator:** Smith David → Snowball Coal Corp; 1981-01-01 to 1982-03-22; source msha-controller-operator-history
- **operator_operates_mine:** Comanche Coal Corp → Mine No 3; 1982-03-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Blankenship Ralph → Comanche Coal Corp; 1982-03-23 to current/open; source msha-controller-operator-history