# Relationship history for MSHA mine 4201928

Current hierarchy: **Marketta  Ashdown → Ashdown Brothers Construction, Inc → Ashdown 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

- **operator_operates_mine:** Ashdown Brothers Construction, Inc → Ashdown Pit; 1985-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mark  Ashdown  et al → Ashdown Pit; 1985-03-01 to 2019-06-23; source msha-controller-operator-history
- **controller_controls_operator:** Mark  Ashdown  et al → Ashdown Brothers Construction, Inc; 1985-03-01 to 2019-06-23; source msha-controller-operator-history
- **controller_controls_operator:** Murray  Ashdown  et al → Ashdown Brothers Construction, Inc; 1985-03-01 to 2019-06-23; source msha-controller-operator-history
- **controller_controls_mine:** Marketta  Ashdown → Ashdown Pit; 2019-06-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Marketta  Ashdown → Ashdown Brothers Construction, Inc; 2019-06-24 to current/open; source msha-controller-operator-history