# Relationship history for MSHA mine 0504478

Current hierarchy: **William  Kobobel → Idaho Creek Gravel Company → IDAHO CREEK GRAVEL CO**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Idaho Creek Gravel Company → IDAHO CREEK GRAVEL CO; 1992-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** William  Kobobel → IDAHO CREEK GRAVEL CO; 1992-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William  Kobobel → Idaho Creek Gravel Company; 1992-02-01 to current/open; source msha-controller-operator-history