# Relationship history for MSHA mine 3401289

Current hierarchy: **Buzzi S p A → Buzzi Unicem USA → LONE STAR PRYOR PLT MILL & QY**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Lone Star Industries Inc → LONE STAR PRYOR PLT MILL & QY; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** OKC Corp → LONE STAR PRYOR PLT MILL & QY; 1950-01-01 to 1980-10-19; source msha-controller-operator-history
- **operator_operates_mine:** Okc Corp → LONE STAR PRYOR PLT MILL & QY; 1979-01-01 to 1980-05-15; source msha-controller-operator-history
- **controller_controls_operator:** OKC Corp → Okc Corp; 1979-01-01 to 1980-05-15; source msha-controller-operator-history
- **operator_operates_mine:** Lone Star Industries Inc → LONE STAR PRYOR PLT MILL & QY; 1980-05-16 to 2003-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Lone Star Industries Inc → Lone Star Industries Inc; 1980-05-16 to 2003-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Dyckerhoff AG → LONE STAR PRYOR PLT MILL & QY; 1999-10-04 to 2003-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Buzzi Unicem USA → LONE STAR PRYOR PLT MILL & QY; 2004-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Buzzi S p A → LONE STAR PRYOR PLT MILL & QY; 2004-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Buzzi S p A → Buzzi Unicem USA; 2004-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dyckerhoff AG → Buzzi Unicem USA; 2004-01-01 to 2003-12-31; source msha-controller-operator-history