# Relationship history for MSHA mine 0504038

Current hierarchy: **Siegrist Construction Company → Burnett Construction Company → Perkins Pit**

- 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:** Siegrist Construction Company Et Al → Perkins Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Burnett Construction Company → Perkins Pit; 1985-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Siegrist Construction Company Et Al → Burnett Construction Company; 1985-05-01 to current/open; source msha-controller-operator-history