# Relationship history for MSHA mine 4606466

Current hierarchy: **Langford James E → Upco Coal Inc → Upco Ward Tipple**

- 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

- **operator_operates_mine:** B R J Inc → Upco Ward Tipple; 1981-12-01 to 1989-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Warner Barbara → Upco Ward Tipple; 1981-12-01 to 1989-07-19; source msha-controller-operator-history
- **controller_controls_operator:** Warner Barbara → B R J Inc; 1981-12-01 to 1989-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Langford James E → Upco Ward Tipple; 1985-01-14 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Upco Coal Inc → Upco Ward Tipple; 1989-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Langford James E → Upco Coal Inc; 1989-07-20 to current/open; source msha-controller-operator-history