# Relationship history for MSHA mine 1400062

Current hierarchy: **Michael M  Beachner → Harry Byers & Sons Inc → Harry Byers & Sons Inc**

- 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:** Harry Byers & Sons Inc → Harry Byers & Sons Inc; 1950-01-01 to 2001-03-18; source msha-controller-operator-history
- **controller_controls_mine:** George A  Burkhart → Harry Byers & Sons Inc; 1950-01-01 to 2001-03-18; source msha-controller-operator-history
- **controller_controls_operator:** George A  Burkhart → Harry Byers & Sons Inc; 1950-01-01 to 2001-03-18; source msha-controller-operator-history
- **operator_operates_mine:** Harry Byers & Sons Inc → Harry Byers & Sons Inc; 2001-03-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Michael M  Beachner → Harry Byers & Sons Inc; 2001-03-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael M  Beachner → Harry Byers & Sons Inc; 2001-03-19 to current/open; source msha-controller-operator-history