# Relationship history for MSHA mine 3609071

Current hierarchy: **James R  Mayberry → Mayberry Sand & Gravel Inc → Werner 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:** Mayberry Sand & Gravel Inc → Werner Mine; 2002-04-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** James R  Mayberry → Werner Mine; 2002-04-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James R  Mayberry → Mayberry Sand & Gravel Inc; 2002-04-05 to current/open; source msha-controller-operator-history