# Relationship history for MSHA mine 1201915

Current hierarchy: **Davis Russell E → Blackfoot Inc → Blackfoot Auger**

- 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:** Davis Russell E → Blackfoot Auger; 1981-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Blackfoot Inc → Blackfoot Auger; 1983-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Davis Russell E → Blackfoot Inc; 1983-08-01 to current/open; source msha-controller-operator-history