# Relationship history for MSHA mine 0801339

Current hierarchy: **Fred M  Derr → Frederick Derr & Co., Inc. → Wilderness Pit**

- 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:** Frederick Derr & Co., Inc. → Wilderness Pit; 2005-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Fred M  Derr et al → Wilderness Pit; 2005-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fred M  Derr et al → Frederick Derr & Co., Inc.; 2005-04-28 to current/open; source msha-controller-operator-history