# Relationship history for MSHA mine 3607039

Current hierarchy: **Roger A  Thomas; Miriam R  Thomas → Ramm Coal Company → Thomas**

- 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:** Ramm Coal Company → Thomas; 1980-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Miriam R  Thomas et al → Thomas; 1980-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Miriam R  Thomas et al → Ramm Coal Company; 1980-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roger A  Thomas et al → Ramm Coal Company; 1980-09-01 to current/open; source msha-controller-operator-history