# Relationship history for MSHA mine 1900556

Current hierarchy: **Pacheco Robert B → Falmouth Concrete & Building Supplies Inc → Falmouth Concrete & Building Supplies P/**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Falmouth Concrete & Building Supplies Inc → Falmouth Concrete & Building Supplies P/; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Pacheco Robert B → Falmouth Concrete & Building Supplies P/; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Pacheco Robert B → Falmouth Concrete & Building Supplies Inc; 1950-01-01 to current/open; source msha-controller-operator-history