# Relationship history for MSHA mine 4404801

Current hierarchy: **Seaboard Coal Mining Corp → Tazewell Coal Equipment Partnership → No 1 Loading Dock**

- 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:** Tazewell Coal Equipment Partnership → No 1 Loading Dock; 1977-04-01 to 1979-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Minco Corp & Westbury Development Corp → No 1 Loading Dock; 1977-04-01 to 1979-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Minco Corp & Westbury Development Corp → Tazewell Coal Equipment Partnership; 1977-04-01 to 1979-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Tazewell Coal Equipment Partnership → No 1 Loading Dock; 1980-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Seaboard Coal Mining Corp → No 1 Loading Dock; 1980-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Seaboard Coal Mining Corp → Tazewell Coal Equipment Partnership; 1980-01-01 to current/open; source msha-controller-operator-history