# Relationship history for MSHA mine 2500968

Current hierarchy: **Decker Leon & Urban Behrens → Decker Sand & Gravel → Warnke 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

- **operator_operates_mine:** Decker Sand & Gravel → Warnke Pit; 1980-04-01 to 1986-11-09; source msha-controller-operator-history
- **controller_controls_mine:** Decker Leon → Warnke Pit; 1980-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Decker Leon → Decker Sand & Gravel; 1980-04-01 to 1986-11-09; source msha-controller-operator-history
- **operator_operates_mine:** Decker Sand & Gravel → Warnke Pit; 1986-11-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Decker Leon & Urban Behrens → Warnke Pit; 1986-11-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Decker Leon & Urban Behrens → Decker Sand & Gravel; 1986-11-10 to current/open; source msha-controller-operator-history