# Relationship history for MSHA mine 3303845

Current hierarchy: **Salonica Frank T → Jeffco Sales & Mining Company → Y & O Road Mine**

- 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:** Salonica Frank T → Y & O Road Mine; 1975-01-06 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Jeffco Sales & Mining Company → Y & O Road Mine; 1980-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Salonica Frank T → Jeffco Sales & Mining Company; 1980-12-01 to current/open; source msha-controller-operator-history