# Relationship history for MSHA mine 4404920

Current hierarchy: **Justus Donald → T & M Mining Inc → 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** N R Coal Corp → No 1; 1977-12-01 to 1978-05-08; source msha-controller-operator-history
- **controller_controls_mine:** Nichols J H & Storia Rife → No 1; 1977-12-01 to 1978-05-08; source msha-controller-operator-history
- **controller_controls_operator:** Nichols J H & Storia Rife → N R Coal Corp; 1977-12-01 to 1978-05-08; source msha-controller-operator-history
- **operator_operates_mine:** T & M Mining Inc → No 1; 1978-05-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Justus Donald Et Al → No 1; 1978-05-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Justus Donald Et Al → T & M Mining Inc; 1978-05-09 to current/open; source msha-controller-operator-history