# Relationship history for MSHA mine 2003517

Current hierarchy: **Dave  Culver → Culver Excavating, Inc. → Grand River**

- 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

- **controller_controls_mine:** Dave  Culver → Grand River; 1998-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Culver Excavating, Inc. → Grand River; 2015-09-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dave  Culver → Culver Excavating, Inc.; 2015-09-10 to current/open; source msha-controller-operator-history