# Relationship history for MSHA mine 3608312

Current hierarchy: **American Metals & Coal International Inc → Senate Coal Mines Inc → Cambria**

- 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:** Senate Coal Mines Inc → Cambria; 1992-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** American Metals & Coal International Inc → Cambria; 1992-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** American Metals & Coal International Inc → Senate Coal Mines Inc; 1992-01-01 to current/open; source msha-controller-operator-history