# Relationship history for MSHA mine 4608975

Current hierarchy: **James River Coal Company → Hampden Coal Company, Inc. → No. 4 Deep 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** International Industries Inc → No. 4 Deep Mine; 1987-11-01 to 2011-04-17; source msha-controller-operator-history
- **operator_operates_mine:** Hampden Coal Company, Inc. → No. 4 Deep Mine; 2002-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** International Industries Inc → Hampden Coal Company, Inc.; 2002-11-01 to 2011-04-17; source msha-controller-operator-history
- **controller_controls_mine:** James River Coal Company → No. 4 Deep Mine; 2011-04-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James River Coal Company → Hampden Coal Company, Inc.; 2011-04-18 to current/open; source msha-controller-operator-history