# Relationship history for MSHA mine 1800404

Current hierarchy: **Porto Family Dynasty Trust 1; Brian A Porto et  al → Tri-State Stone & Building Supply Inc. → Carderock Quarries**

- 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:** Tri-State Stone & Building Supply Inc. → Carderock Quarries; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Brian A Porto et  al → Carderock Quarries; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brian A Porto et  al → Tri-State Stone & Building Supply Inc.; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Porto Family Dynasty Trust 1 et al → Tri-State Stone & Building Supply Inc.; 1950-01-01 to current/open; source msha-controller-operator-history