# Relationship history for MSHA mine 4002046

Current hierarchy: **Fletcher Marvin H Jr → Big Fork Mining Company Inc → Gruetli No 2 Strip**

- 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:** Fletcher Marvin H Jr → Gruetli No 2 Strip; 1975-11-25 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Luther Nabors Coal Company → Gruetli No 2 Strip; 1976-04-29 to 1976-10-01; source msha-controller-operator-history
- **controller_controls_mine:** Nabors Joe D & Luther → Gruetli No 2 Strip; 1976-04-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nabors Joe D & Luther → Luther Nabors Coal Company; 1976-04-29 to 1976-10-01; source msha-controller-operator-history
- **operator_operates_mine:** Big Fork Mining Company Inc → Gruetli No 2 Strip; 1976-10-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fletcher Marvin H Jr → Big Fork Mining Company Inc; 1976-10-02 to current/open; source msha-controller-operator-history