# Relationship history for MSHA mine 0301877

Current hierarchy: **Noel R  McGrew → Noel R McGrew → OQC-160**

- 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:** Noel R  McGrew → OQC-160; 1989-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Noel R McGrew → OQC-160; 2003-07-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Noel R  McGrew → Noel R McGrew; 2003-07-02 to current/open; source msha-controller-operator-history