# Relationship history for MSHA mine 3605410

Current hierarchy: **Marmon Group Inc → G M & W Coal Company Inc → Grove #4 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:** C Kenneth  Crotsley → Grove #4 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** G M & W Coal Company Inc → Grove #4 Mine; 1975-06-23 to 1976-12-08; source msha-controller-operator-history
- **controller_controls_operator:** C Kenneth  Crotsley → G M & W Coal Company Inc; 1975-06-23 to 1976-12-08; source msha-controller-operator-history
- **operator_operates_mine:** G M & W Coal Company Inc → Grove #4 Mine; 1976-12-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Marmon Group Inc → Grove #4 Mine; 1976-12-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Marmon Group Inc → G M & W Coal Company Inc; 1976-12-09 to current/open; source msha-controller-operator-history