# Relationship history for MSHA mine 4703286

Current hierarchy: **Robert  Ecker → J & E Construction Company, Inc. → Nordberg HP-400**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** James  Ecker → Nordberg HP-400; 1950-01-01 to 2022-10-15; source msha-controller-operator-history
- **operator_operates_mine:** J & E Construction Company Inc → Nordberg HP-400; 2001-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James  Ecker → J & E Construction Company Inc; 2001-08-01 to 2022-10-15; source msha-controller-operator-history
- **controller_controls_mine:** Robert  Ecker → Nordberg HP-400; 2022-10-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert  Ecker → J & E Construction Company Inc; 2022-10-16 to current/open; source msha-controller-operator-history