# Relationship history for MSHA mine 1509548

Current hierarchy: **American Industries & Resources Corp → Triex Excavating Company Inc → No 2 Surface**

- 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:** Triex Excavating Inc → No 2 Surface; 1976-03-01 to 1977-12-22; source msha-controller-operator-history
- **controller_controls_mine:** Scarbrough John → No 2 Surface; 1976-03-01 to 1977-12-22; source msha-controller-operator-history
- **controller_controls_operator:** Scarbrough John → Triex Excavating Inc; 1976-03-01 to 1977-12-22; source msha-controller-operator-history
- **operator_operates_mine:** Triex Excavating Company Inc → No 2 Surface; 1977-12-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** American Industries & Resources Corp → No 2 Surface; 1977-12-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** American Industries & Resources Corp → Triex Excavating Company Inc; 1977-12-23 to current/open; source msha-controller-operator-history