# Relationship history for MSHA mine 6900001

Current hierarchy: **Mitsubishi Corp → Hawaiian Rock Products → Obyan Quarry**

- 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:** Hawaiian Rock Products → Obyan Quarry; 2015-12-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jerrold Clay  Johnson → Obyan Quarry; 2015-12-22 to 2026-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Jerrold Clay  Johnson → Hawaiian Rock Products; 2015-12-22 to 2026-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Mitsubishi Corp → Obyan Quarry; 2026-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mitsubishi Corp → Hawaiian Rock Products; 2026-07-01 to current/open; source msha-controller-operator-history