# Relationship history for MSHA mine 3002376

Current hierarchy: **Robert  Dobie → Dobie Brothers Inc → KOLLER PIT**

- 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:** Essex County-Ny → KOLLER PIT; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Essex County Highway Department → KOLLER PIT; 1979-01-01 to 1990-12-04; source msha-controller-operator-history
- **controller_controls_operator:** Essex County-Ny → Essex County Highway Department; 1979-01-01 to 1990-12-04; source msha-controller-operator-history
- **operator_operates_mine:** Dobie Brothers Inc → KOLLER PIT; 1990-12-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robert  Dobie → KOLLER PIT; 1990-12-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert  Dobie → Dobie Brothers Inc; 1990-12-05 to current/open; source msha-controller-operator-history