# Relationship history for MSHA mine 4001148

Current hierarchy: **Shackelford Dallas & Moore Clyde W → White Oak Coal Corp → #1 Tenn Strip**

- 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:** S A M Coal Company Inc → #1 Tenn Strip; 1950-01-01 to 1983-02-20; source msha-controller-operator-history
- **controller_controls_mine:** Fred  Morgenstern et al → #1 Tenn Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fred  Morgenstern et al → S A M Coal Company Inc; 1950-01-01 to 1983-02-20; source msha-controller-operator-history
- **controller_controls_operator:** David  Morgenstern et al → S A M Coal Company Inc; 1950-01-01 to 1983-02-20; source msha-controller-operator-history
- **operator_operates_mine:** White Oak Coal Corp → #1 Tenn Strip; 1983-02-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Shackelford Dallas & Moore Clyde W → #1 Tenn Strip; 1983-02-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shackelford Dallas & Moore Clyde W → White Oak Coal Corp; 1983-02-21 to current/open; source msha-controller-operator-history