# Relationship history for MSHA mine 4703679

Current hierarchy: **Mathy Construction Company → Milestone Materials Div. Mathy Construction Co. → Plant #91**

- 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:** Mathy Construction Company → Plant #91; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Milestone Materials Div. Mathy Construction Co. → Plant #91; 2013-02-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mathy Construction Company → Milestone Materials Div. Mathy Construction Co.; 2013-02-16 to current/open; source msha-controller-operator-history