# Relationship history for MSHA mine 4501941

Current hierarchy: **Michael P  Shaw → Puget Sound Surfacers Inc → Stilly Pass Pit And Portable 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:** U S Forest Service → Stilly Pass Pit And Portable Mill; 1950-01-01 to 1980-10-20; source msha-controller-operator-history
- **controller_controls_mine:** United States Government → Stilly Pass Pit And Portable Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United States Government → U S Forest Service; 1950-01-01 to 1980-10-20; source msha-controller-operator-history
- **controller_controls_mine:** Michael P  Shaw → Stilly Pass Pit And Portable Mill; 1979-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Puget Sound Surfacers Inc → Stilly Pass Pit And Portable Mill; 1980-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael P  Shaw → Puget Sound Surfacers Inc; 1980-10-21 to current/open; source msha-controller-operator-history