# Relationship history for MSHA mine 3606398

Current hierarchy: **Rebuck Donald R Sr → A & D Coal Company → Zero Vein Slope**

- 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:** Snyder Coal Company → Zero Vein Slope; 1977-04-01 to 1984-06-14; source msha-controller-operator-history
- **controller_controls_mine:** Snyder Dennis Et Al → Zero Vein Slope; 1977-04-01 to 1988-10-31; source msha-controller-operator-history
- **controller_controls_operator:** Snyder Dennis Et Al → Snyder Coal Company; 1977-04-01 to 1984-06-14; source msha-controller-operator-history
- **controller_controls_mine:** Rebuck Donald R Sr Et Al → Zero Vein Slope; 1984-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** A & D Coal Company → Zero Vein Slope; 1984-06-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rebuck Donald R Sr Et Al → A & D Coal Company; 1984-06-15 to current/open; source msha-controller-operator-history