# Relationship history for MSHA mine 0300399

Current hierarchy: **Crisp J J → J J Crisp Gravel Sales → Crisp 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** J J Crisp Gravel Sales → Crisp Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Crisp J J → Crisp Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Crisp J J → J J Crisp Gravel Sales; 1950-01-01 to current/open; source msha-controller-operator-history