# Relationship history for MSHA mine 4202761

Current hierarchy: **B Maray  Bringhurst; Jim  Bringhurst → Terra Materials → Terra Portable**

- 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:** Terra Materials → Terra Portable; 2024-07-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jim  Bringhurst et al → Terra Portable; 2024-07-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jim  Bringhurst et al → Terra Materials; 2024-07-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** B Maray  Bringhurst et al → Terra Materials; 2024-07-08 to current/open; source msha-controller-operator-history