# Relationship history for MSHA mine 4801346

Current hierarchy: **Union Pacific Corp → Union Pacific Minerals Inc → Bear River Operation**

- 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:** Union Pacific Minerals Inc → Bear River Operation; 1981-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Union Pacific Corp → Bear River Operation; 1981-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Union Pacific Corp → Union Pacific Minerals Inc; 1981-05-01 to current/open; source msha-controller-operator-history