# Relationship history for MSHA mine 4300299

Current hierarchy: **Trampas  Demers → SHELBURNE LIMESTONE CORP → MIDDLEBURY 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:** Dennis R  Demers → MIDDLEBURY QUARRY; 1950-01-01 to 2017-04-30; source msha-controller-operator-history
- **operator_operates_mine:** L A Demers → MIDDLEBURY QUARRY; 1978-03-09 to 1997-09-01; source msha-controller-operator-history
- **controller_controls_mine:** Lucien A  Demers → MIDDLEBURY QUARRY; 1978-03-09 to 1997-09-01; source msha-controller-operator-history
- **controller_controls_operator:** Lucien A  Demers → L A Demers; 1978-03-09 to 1997-09-01; source msha-controller-operator-history
- **operator_operates_mine:** Shelburne Limestone Corp → MIDDLEBURY QUARRY; 1997-09-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dennis R  Demers → Shelburne Limestone Corp; 1997-09-02 to 2017-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Trampas  Demers → MIDDLEBURY QUARRY; 2017-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Trampas  Demers → Shelburne Limestone Corp; 2017-05-01 to current/open; source msha-controller-operator-history