# Relationship history for MSHA mine 0504843

Current hierarchy: **Gerald W  Korinek → Korinek Sand & Gravel → Korinek Sand and Gravel**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Gerald W  Korinek → Korinek Sand and Gravel; 1986-02-11 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Korinek Trout Farm → Korinek Sand and Gravel; 2006-03-16 to 2011-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Fred L  Korinek → Korinek Sand and Gravel; 2006-03-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fred L  Korinek → Korinek Trout Farm; 2006-03-16 to 2011-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Korinek Sand & Gravel → Korinek Sand and Gravel; 2012-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gerald W  Korinek → Korinek Sand & Gravel; 2012-01-01 to current/open; source msha-controller-operator-history