# Relationship history for MSHA mine 0203221

Current hierarchy: **Verl  Farnsworth → Northern Arizona Materials Corp → Brothers Mine**

- 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

- **operator_operates_mine:** Northern Arizona Materials Corp → Brothers Mine; 2008-03-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Verl  Farnsworth et al → Brothers Mine; 2008-03-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Verl  Farnsworth et al → Northern Arizona Materials Corp; 2008-03-18 to current/open; source msha-controller-operator-history