# Relationship history for MSHA mine 4404135

Current hierarchy: **Justus Stewart & Robert → K & H Coal Company Inc → No 2 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

- **operator_operates_mine:** Dean-O Coal Company → No 2 Mine; 1975-08-13 to 1988-12-05; source msha-controller-operator-history
- **controller_controls_mine:** Justus Jeffrey → No 2 Mine; 1975-08-13 to 1988-12-05; source msha-controller-operator-history
- **controller_controls_operator:** Justus Jeffrey → Dean-O Coal Company; 1975-08-13 to 1988-12-05; source msha-controller-operator-history
- **controller_controls_mine:** Keen Boyd → No 2 Mine; 1984-08-23 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** K & H Coal Company Inc → No 2 Mine; 1988-12-06 to 1991-08-04; source msha-controller-operator-history
- **controller_controls_operator:** Keen Boyd → K & H Coal Company Inc; 1988-12-06 to 1991-08-04; source msha-controller-operator-history
- **operator_operates_mine:** K & H Coal Company Inc → No 2 Mine; 1991-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Justus Stewart & Robert → No 2 Mine; 1991-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Justus Stewart & Robert → K & H Coal Company Inc; 1991-08-05 to current/open; source msha-controller-operator-history