# Relationship history for MSHA mine 0202353

Current hierarchy: **Ashworth J Michael → Pbr Minerals Inc → Contention**

- 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:** Cochise Silver Mines Inc → Contention; 1987-01-01 to 1987-10-25; source msha-controller-operator-history
- **controller_controls_mine:** Frank  Magini → Contention; 1987-01-01 to 1987-10-25; source msha-controller-operator-history
- **controller_controls_operator:** Frank  Magini → Cochise Silver Mines Inc; 1987-01-01 to 1987-10-25; source msha-controller-operator-history
- **operator_operates_mine:** P B R Minerals Inc → Contention; 1987-10-26 to 1988-08-15; source msha-controller-operator-history
- **controller_controls_mine:** Harper Raymond A Et Al → Contention; 1987-10-26 to 1988-08-15; source msha-controller-operator-history
- **controller_controls_operator:** Harper Raymond A Et Al → P B R Minerals Inc; 1987-10-26 to 1988-08-15; source msha-controller-operator-history
- **operator_operates_mine:** Pbr Minerals Inc → Contention; 1988-08-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ashworth J Michael → Contention; 1988-08-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ashworth J Michael → Pbr Minerals Inc; 1988-08-16 to current/open; source msha-controller-operator-history