# Relationship history for MSHA mine 3502925

Current hierarchy: **Gross Gene → Gross & Hanson → Mc Coy Creek Rock 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Keppinger Inc → Mc Coy Creek Rock Pit; 1979-01-01 to 1979-08-20; source msha-controller-operator-history
- **controller_controls_mine:** Keppinger Inc → Mc Coy Creek Rock Pit; 1979-01-01 to 1979-08-20; source msha-controller-operator-history
- **controller_controls_operator:** Keppinger Inc → Keppinger Inc; 1979-01-01 to 1979-08-20; source msha-controller-operator-history
- **operator_operates_mine:** Gross & Hanson → Mc Coy Creek Rock Pit; 1979-08-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gross Gene → Mc Coy Creek Rock Pit; 1979-08-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gross Gene → Gross & Hanson; 1979-08-21 to current/open; source msha-controller-operator-history