# Relationship history for MSHA mine 0102236

Current hierarchy: **Frost Carl → Number One Mining Company Inc → Hull 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

- **operator_operates_mine:** Number One Mining Company Inc → Hull Mine; 1980-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Frost Carl → Hull Mine; 1980-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Frost Carl → Number One Mining Company Inc; 1980-08-01 to current/open; source msha-controller-operator-history