# Relationship history for MSHA mine 3602885

Current hierarchy: **Great American Coal Company → Northwest Mining Company Inc → Murrin Stripping**

- 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:** Northwest Mining Company Inc → Murrin Stripping; 1950-01-01 to 1973-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Gillen Thomas J → Murrin Stripping; 1950-01-01 to 1973-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Gillen Thomas J → Northwest Mining Company Inc; 1950-01-01 to 1973-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Northwest Mining Company Inc → Murrin Stripping; 1974-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Great American Coal Company → Murrin Stripping; 1974-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Great American Coal Company → Northwest Mining Company Inc; 1974-01-01 to current/open; source msha-controller-operator-history