# Relationship history for MSHA mine 1002037

Current hierarchy: **Nathan  Robinson → Lone Pine Natural Stone, LLC → Birch Creek**

- 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:** Sawtooth Stone LLC → Birch Creek; 2003-03-26 to 2026-04-19; source msha-controller-operator-history
- **controller_controls_mine:** Bruce  Mitchell → Birch Creek; 2003-03-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bruce  Mitchell → Sawtooth Stone LLC; 2003-03-26 to 2026-04-19; source msha-controller-operator-history
- **controller_controls_operator:** Carl  Borgstrom → Sawtooth Stone LLC; 2003-03-26 to 2026-04-19; source msha-controller-operator-history
- **operator_operates_mine:** Lone Pine Natural Stone, LLC → Birch Creek; 2026-04-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Nathan  Robinson → Birch Creek; 2026-04-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nathan  Robinson → Lone Pine Natural Stone, LLC; 2026-04-20 to current/open; source msha-controller-operator-history