# Relationship history for MSHA mine 2103091

Current hierarchy: **William  Brielmaier → Brielmaier Aggregates Inc → PORTABLE CRUSHING III**

- 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:** William  Brielmaier → PORTABLE CRUSHING III; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Brielmaier Aggregates Inc → PORTABLE CRUSHING III; 1995-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William  Brielmaier → Brielmaier Aggregates Inc; 1995-03-01 to current/open; source msha-controller-operator-history