# Relationship history for MSHA mine 3000074

Current hierarchy: **CRH PLC → Tilcon New York Inc → Tomkins Cove 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Martin Marietta Aggregates → Tomkins Cove Quarry; 1950-01-01 to 1978-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Tomkins Cove Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1950-01-01 to 1978-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Hudson River Aggregates Inc → Tomkins Cove Quarry; 1978-04-01 to 1981-01-25; source msha-controller-operator-history
- **controller_controls_mine:** Boyle Jay B → Tomkins Cove Quarry; 1978-04-01 to 1981-01-25; source msha-controller-operator-history
- **controller_controls_operator:** Boyle Jay B → Hudson River Aggregates Inc; 1978-04-01 to 1981-01-25; source msha-controller-operator-history
- **operator_operates_mine:** Tilcon New York Inc → Tomkins Cove Quarry; 1981-01-26 to 1996-09-08; source msha-controller-operator-history
- **controller_controls_mine:** BTR PLC → Tomkins Cove Quarry; 1981-01-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** BTR PLC → Tilcon New York Inc; 1981-01-26 to 1996-09-08; source msha-controller-operator-history
- **operator_operates_mine:** Tilcon New York Inc → Tomkins Cove Quarry; 1996-09-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Tomkins Cove Quarry; 1996-09-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Tilcon New York Inc; 1996-09-09 to current/open; source msha-controller-operator-history