# Relationship history for MSHA mine 3200983

Current hierarchy: **Art  Mariner → Mariner Construction Inc → Engdahl Pit**

- 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

- **controller_controls_mine:** Art  Mariner et al → Engdahl Pit; 1997-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mariner Construction Inc → Engdahl Pit; 2012-07-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Art  Mariner et al → Mariner Construction Inc; 2012-07-02 to current/open; source msha-controller-operator-history