# Relationship history for MSHA mine 2800670

Current hierarchy: **CRH PLC → Tilcon New York Inc → Byram Aggregates**

- 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:** Byram Crushed Stone Corp → Byram Aggregates; 1950-01-01 to 1999-06-30; source msha-controller-operator-history
- **controller_controls_mine:** George M  Kero → Byram Aggregates; 1950-01-01 to 1999-06-30; source msha-controller-operator-history
- **controller_controls_operator:** George M  Kero → Byram Crushed Stone Corp; 1950-01-01 to 1999-06-30; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Byram Aggregates; 1996-09-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Tilcon New York Inc → Byram Aggregates; 1999-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Tilcon New York Inc; 1999-07-01 to current/open; source msha-controller-operator-history