# Relationship history for MSHA mine 4200481

Current hierarchy: **Shumway Robert → Bob Shumway Mining → Big Buck 12**

- 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:** T S & R Mining Inc → Big Buck 12; 1950-01-01 to 1984-12-26; source msha-controller-operator-history
- **controller_controls_mine:** Rockwell Roy J-Merlyn Stainbrook Et Al → Big Buck 12; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rockwell Roy J-Merlyn Stainbrook Et Al → T S & R Mining Inc; 1950-01-01 to 1984-12-26; source msha-controller-operator-history
- **controller_controls_mine:** Shumway Gary → Big Buck 12; 1982-11-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Western Key Enterprise → Big Buck 12; 1984-12-27 to 1988-07-10; source msha-controller-operator-history
- **controller_controls_operator:** Shumway Gary → Western Key Enterprise; 1984-12-27 to 1988-07-10; source msha-controller-operator-history
- **controller_controls_mine:** Shumway Robert → Big Buck 12; 1987-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bob Shumway Mining → Big Buck 12; 1988-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shumway Robert → Bob Shumway Mining; 1988-07-11 to current/open; source msha-controller-operator-history