# Relationship history for MSHA mine 1600867

Current hierarchy: **Diez Stanley → Material Producers Inc → Material Producers Incorporated**

- 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:** I C Sand & Gravel Inc → Material Producers Incorporated; 1950-01-01 to 1981-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Comeaux Jerry R → Material Producers Incorporated; 1950-01-01 to 1981-07-19; source msha-controller-operator-history
- **controller_controls_operator:** Comeaux Jerry R → I C Sand & Gravel Inc; 1950-01-01 to 1981-07-19; source msha-controller-operator-history
- **operator_operates_mine:** Material Producers Inc → Material Producers Incorporated; 1981-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Diez Stanley → Material Producers Incorporated; 1981-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Diez Stanley → Material Producers Inc; 1981-07-20 to current/open; source msha-controller-operator-history