# Relationship history for MSHA mine 3602780

Current hierarchy: **Snyder Marlin L → Marlin L Snyder Coal Company → Snyder 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Marlin L Snyder Coal Company → Snyder Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Snyder Marlin L → Snyder Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Snyder Marlin L → Marlin L Snyder Coal Company; 1950-01-01 to current/open; source msha-controller-operator-history