# Relationship history for MSHA mine 4703063

Current hierarchy: **Keith E  Hammersley → Hammersley Stone Company Inc → HSC Lacy Road Quarries 1 and 2**

- 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:** Keith E  Hammersley → HSC Lacy Road Quarries 1 and 2; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hammersley Stone Company Inc → HSC Lacy Road Quarries 1 and 2; 1995-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Keith E  Hammersley → Hammersley Stone Company Inc; 1995-11-01 to current/open; source msha-controller-operator-history