# Relationship history for MSHA mine 0102444

Current hierarchy: **Willingham Patrick → Southcoal Mining Corp → Dogwood**

- 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:** Tenncor Land & Development Corp Inc → Dogwood; 1981-10-01 to 1983-04-20; source msha-controller-operator-history
- **controller_controls_mine:** Izdebski Richard J → Dogwood; 1981-10-01 to 1983-04-20; source msha-controller-operator-history
- **controller_controls_operator:** Izdebski Richard J → Tenncor Land & Development Corp Inc; 1981-10-01 to 1983-04-20; source msha-controller-operator-history
- **operator_operates_mine:** Southcoal Mining Corp → Dogwood; 1983-04-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Willingham Patrick → Dogwood; 1983-04-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Willingham Patrick → Southcoal Mining Corp; 1983-04-21 to current/open; source msha-controller-operator-history