# Relationship history for MSHA mine 4403928

Current hierarchy: **Lawson Charles G → Chaparal Mining Company Inc → Surface Mine No 2**

- 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:** Lawson Charles G → Surface Mine No 2; 1974-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Chaparal Mining Company Inc → Surface Mine No 2; 1975-01-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lawson Charles G → Chaparal Mining Company Inc; 1975-01-08 to current/open; source msha-controller-operator-history