# Relationship history for MSHA mine 2301919

Current hierarchy: **Mertens Construction Company Inc → Mertens Construction Company Inc → Huntsville 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

- **controller_controls_mine:** Mertens Construction Company Inc → Huntsville Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Huntsville Stone Inc → Huntsville Quarry; 1985-06-01 to 1986-03-23; source msha-controller-operator-history
- **controller_controls_mine:** Jacoby James Victor Et Al → Huntsville Quarry; 1985-06-01 to 1986-03-23; source msha-controller-operator-history
- **controller_controls_operator:** Jacoby James Victor Et Al → Huntsville Stone Inc; 1985-06-01 to 1986-03-23; source msha-controller-operator-history
- **operator_operates_mine:** Mertens Construction Company Inc → Huntsville Quarry; 1986-03-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mertens Construction Company Inc → Mertens Construction Company Inc; 1986-03-24 to current/open; source msha-controller-operator-history