# Relationship history for MSHA mine 1506264

Current hierarchy: **Sterling Enterprises Inc; The Allen Company Inc → Lexington Quarry Company → Lexington Quarry**

- 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:** Lexington Quarry Company → Lexington Quarry; 1950-01-01 to 1990-06-28; source msha-controller-operator-history
- **controller_controls_mine:** George  Carey et al → Lexington Quarry; 1950-01-01 to 1990-06-28; source msha-controller-operator-history
- **controller_controls_operator:** George  Carey et al → Lexington Quarry Company; 1950-01-01 to 1990-06-28; source msha-controller-operator-history
- **operator_operates_mine:** Lexington Quarry Company → Lexington Quarry; 1990-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Sterling Enterprises Inc et al → Lexington Quarry; 1990-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sterling Enterprises Inc et al → Lexington Quarry Company; 1990-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** The Allen Company Inc et al → Lexington Quarry Company; 1990-06-29 to current/open; source msha-controller-operator-history