# Relationship history for MSHA mine 1514689

Current hierarchy: **Hermrs C W → Nkg Marine Service Inc → Onton Dock Inc**

- 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:** Onton Dock Inc → Onton Dock Inc; 1984-06-01 to 1991-05-14; source msha-controller-operator-history
- **controller_controls_mine:** Carlisle Chester → Onton Dock Inc; 1984-06-01 to 1991-05-14; source msha-controller-operator-history
- **controller_controls_operator:** Carlisle Chester → Onton Dock Inc; 1984-06-01 to 1991-05-14; source msha-controller-operator-history
- **operator_operates_mine:** Nkg Marine Service Inc → Onton Dock Inc; 1991-05-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hermrs C W → Onton Dock Inc; 1991-05-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hermrs C W → Nkg Marine Service Inc; 1991-05-15 to current/open; source msha-controller-operator-history