# Relationship history for MSHA mine 4606768

Current hierarchy: **Lester David A → Golden Decade Coal Inc → Big Blue Auger**

- 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

- **controller_controls_mine:** Lester David A → Big Blue Auger; 1982-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Golden Decade Coal Inc → Big Blue Auger; 1984-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lester David A → Golden Decade Coal Inc; 1984-04-01 to current/open; source msha-controller-operator-history