# Relationship history for MSHA mine 3605661

Current hierarchy: **Ringgold Mines Inc → Markle Bullers Coal Company → Mauk Mine (Strip No 1)**

- 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

- **controller_controls_mine:** Ringgold Mines Inc → Mauk Mine (Strip No 1); 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Markle Bullers Coal Company → Mauk Mine (Strip No 1); 1975-09-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ringgold Mines Inc → Markle Bullers Coal Company; 1975-09-15 to current/open; source msha-controller-operator-history