# Relationship history for MSHA mine 1510578

Current hierarchy: **Marcum Thomas Ray → M & H Coal Inc → No 8 Mine**

- 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

- **controller_controls_mine:** Marcum Thomas Ray → No 8 Mine; 1974-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** M & H Coal Inc → No 8 Mine; 1977-07-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Marcum Thomas Ray → M & H Coal Inc; 1977-07-15 to current/open; source msha-controller-operator-history