# Relationship history for MSHA mine 0503267

Current hierarchy: **Larry E  Smith; Fred R  Langley → National Energy Resources Of Colorado → Las Animas Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** National Energy Resources Of Colorado → Las Animas Mine; 1979-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Fred R  Langley et al → Las Animas Mine; 1979-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fred R  Langley et al → National Energy Resources Of Colorado; 1979-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Larry E  Smith et al → National Energy Resources Of Colorado; 1979-07-01 to current/open; source msha-controller-operator-history