# Relationship history for MSHA mine 1201811

Current hierarchy: **Shand Alexander (Holdings) Ltd → B & Ls Contracting Inc → Blanca 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:** Fossil Fuels Inc → Blanca Mine; 1980-10-01 to 1985-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Rooksby Robert T → Blanca Mine; 1980-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rooksby Robert T → Fossil Fuels Inc; 1980-10-01 to 1985-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Shand Alexander (Holdings) Ltd → Blanca Mine; 1983-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** B & Ls Contracting Inc → Blanca Mine; 1985-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shand Alexander (Holdings) Ltd → B & Ls Contracting Inc; 1985-04-01 to current/open; source msha-controller-operator-history