# Relationship history for MSHA mine 0504603

Current hierarchy: **Deilmann-Haniel & Maschinen-Und Stahlbau Gmbh et a → Frontier-Kemper Constructors Inc → Sylvester Gulch No 1**

- 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

- **operator_operates_mine:** Frontier-Kemper Constructors Inc → Sylvester Gulch No 1; 1997-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Deilmann-Haniel & Maschinen-Und Stahlbau Gmbh et a → Sylvester Gulch No 1; 1997-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Deilmann-Haniel & Maschinen-Und Stahlbau Gmbh et a → Frontier-Kemper Constructors Inc; 1997-07-01 to current/open; source msha-controller-operator-history