# Relationship history for MSHA mine 3100409

Current hierarchy: **Boyd Devon F & Tony → Boyd Contractors & Materials Inc → Catawba River 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

- **operator_operates_mine:** Boyd Contracting & Materials Inc → Catawba River Pit; 1950-01-01 to 1990-03-11; source msha-controller-operator-history
- **controller_controls_mine:** Boyd Max & Harold → Catawba River Pit; 1950-01-01 to 1990-03-11; source msha-controller-operator-history
- **controller_controls_operator:** Boyd Max & Harold → Boyd Contracting & Materials Inc; 1950-01-01 to 1990-03-11; source msha-controller-operator-history
- **operator_operates_mine:** Boyd Contractors & Materials Inc → Catawba River Pit; 1990-03-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Boyd Devon F & Tony → Catawba River Pit; 1990-03-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Boyd Devon F & Tony → Boyd Contractors & Materials Inc; 1990-03-12 to current/open; source msha-controller-operator-history