# Relationship history for MSHA mine 1601415

Current hierarchy: **Eric  Johnson → Highland Rock Company, Inc. → Hornsby Lease**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Maxwell L  Johnson III et al → Hornsby Lease; 1998-10-26 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Gulf Coast Gravel Inc → Hornsby Lease; 2004-08-31 to 2019-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Maxwell L  Johnson III et al → Gulf Coast Gravel Inc; 2004-08-31 to 2019-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Highland Rock Company Inc → Hornsby Lease; 2019-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Eric  Johnson → Hornsby Lease; 2019-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eric  Johnson → Highland Rock Company Inc; 2019-09-01 to current/open; source msha-controller-operator-history