# Relationship history for MSHA mine 2003069

Current hierarchy: **Anne K  Coursey; David T  Marx → Champagne & Marx Excavating Inc → Nordberg Plant**

- 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:** Champagne & Marx Excavating Inc → Nordberg Plant; 1998-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Marx Thomas M → Nordberg Plant; 1998-07-01 to 2013-07-07; source msha-controller-operator-history
- **controller_controls_operator:** Marx Thomas M → Champagne & Marx Excavating Inc; 1998-07-01 to 2013-07-07; source msha-controller-operator-history
- **controller_controls_mine:** Anne K  Coursey et al → Nordberg Plant; 2013-07-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Anne K  Coursey et al → Champagne & Marx Excavating Inc; 2013-07-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David T  Marx et al → Champagne & Marx Excavating Inc; 2013-07-08 to current/open; source msha-controller-operator-history