# Relationship history for MSHA mine 3606939

Current hierarchy: **Elwood  Swank → Split Vein Coal Company Inc → J J G Strip**

- 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:** Elwood  Swank → J J G Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Buckto Corp → J J G Strip; 1980-02-01 to 1985-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Buckley Robert & James Thomas → J J G Strip; 1980-02-01 to 1985-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Buckley Robert & James Thomas → Buckto Corp; 1980-02-01 to 1985-01-31; source msha-controller-operator-history
- **operator_operates_mine:** J J G Coal Company → J J G Strip; 1985-02-01 to 1987-02-24; source msha-controller-operator-history
- **controller_controls_mine:** Geier John → J J G Strip; 1985-02-01 to 1987-02-24; source msha-controller-operator-history
- **controller_controls_operator:** Geier John → J J G Coal Company; 1985-02-01 to 1987-02-24; source msha-controller-operator-history
- **operator_operates_mine:** Split Vein Coal Company Inc → J J G Strip; 1987-02-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Elwood  Swank → Split Vein Coal Company Inc; 1987-02-25 to current/open; source msha-controller-operator-history